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11.
The therapeutic implications of intratumoral regulatory T cells.   总被引:1,自引:0,他引:1  
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PURPOSE: Improved cure rates for children with acute lymphoblastic leukemia (ALL) have resulted from better relapse prediction, using clinical and laboratory features at diagnosis, and more intensive therapy in high-risk patients. More recently, measurements of the variation in the response of malignant lymphoblasts to chemotherapy in vivo have further improved relapse prediction. It is unknown whether the variation in the response of nonmalignant hematologic cells after chemotherapy correlates with the response of lymphoblasts or risk of relapse. PATIENTS AND METHODS: We retrospectively evaluated myelosuppression during induction and consolidation chemotherapy in 227 children uniformly treated for ALL on consecutive Australian and New Zealand Children's Cancer Study Group protocols. The early response to treatment was assessed in a representative subset (n = 62) by determining minimal residual disease (MRD) level by molecular techniques on the end-of-induction bone marrow sample. RESULTS: We found that a slow rate of myeloid recovery at the end of induction chemotherapy, reflected in a low absolute neutrophil count (ANC), was highly predictive of relapse (P < .0001). Additionally, patients with a high end-of-induction MRD level had a high risk of relapse (P = .001). Multivariate analysis confirmed the independent prognostic significance of MRD and ANC at the end of induction chemotherapy (P < .05). There was no significant association between other measures of myelotoxicity and MRD or relapse. CONCLUSION: We conclude that the responses of normal myeloid cells and malignant lymphoblasts to chemotherapy predict outcome by distinct mechanisms. While these results are promising, their use in the clinical setting needs to be examined in a future randomized controlled trial.  相似文献   
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As the proportion of racial, ethnic, and cultural minorities in the United States continues to expand, pediatric emergency medicine providers are increasingly likely to encounter cultural and language barriers in practice. This paper reviews a conceptual framework encompassing the decision to seek emergency care, the process of providing such care, and the adherence to treatment plans and follow-up. The ways in which cultural and language barriers can negatively impact each element of this model are discussed in detail. Specific examples include provider ignorance of dangerous folk beliefs, communication barriers secondary to inappropriate interpreter use, and discriminatory assumptions regarding child abuse, pain management, and sexual activity. The practitioner is then provided with concrete recommendations to reduce these negative effects.  相似文献   
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n = 69) normal; Group B (n= 29), abnormal, severe defects; Group C (n= 56), abnormal, mild–moderate defect. RCA detected 32 defects in Group B: 10 internal carotid (ICA), seven endpoint flaps, two kinks, one dissection; 16 external carotid (ECA), 10 severe endpoint defects and six total occlusion; six common carotid (CCA), five irregular proximal shelfs, one web. Thirty of 32 defects were successfully repaired as confirmed by normal repeat RCA studies; one ECA defect was not repaired and the ICA dissection was irreparable. In Group C, 67 mild–moderate defects were identified, but not corrected. These included <30% stenosis in the ICA (12), ECA (18), CCA (24), and vein patch corrugation or irregularity (13). For the entire series the postoperative ICA occlusion rate was 2% (3/154), stroke rate 2.6% (4/154), and a subsequent >50% restenosis rate of 7% (11/154). The yield from routine carotid completion arteriograms was significant, with 19% of studies identifying a severe defect that required repair. Although the difference in stroke rates and restenosis between the different groups did not reach statistical significance, patients with normal intraoperative arteriograms initially or after correction of a significant RCA defect had no early carotid occlusion (p= 0.05, Fisher's exact test) compared to patients with residual RCA defects. All early carotid occlusions occurred in patients with unrepaired defects. We conclude that RCA is an important method of quality control after CEA and exerts a subtle, but real, reduction in postoperative complications.  相似文献   
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OBJECTIVE: Compare the immunological and echocardiographic data of decellularized versus cryopreserved allografts used for RVOT reconstruction during Ross operation. METHODS: From 16/01/03 thru 07/10/03, 20 Ross operations were performed using decellularized (n=11) or cryopreserved (n=9) allografts. Echocardiography was done at discharge, 1, 3, 6 and 12 months and annually thereafter. Samples for determination of antibodies against HLA class I and II were obtained preoperatively and at days 5, 10, 30, 90 and 180 postoperatively. These samples were tested by the ELISA method in LAT-M dishes (unspecific) for identification of circulating antibodies and the results expressed as mean sample values (Is=DO/cutoff). If positive, LAT-E (specific) was performed and PRA levels determined. RESULTS: There was no mortality. Cryopreserved allografts showed marked Is values elevations for class I and II antibodies which started at the first month and remained elevated up to 6 months. In contrast, of the patients receiving decellularized allografts, seven remained negative, two patients had only marginal elevation of class I antibodies and two patients showed abnormal elevations of PRA levels. This response happened earlier than in the cryopreserved group, starting on the 5th postoperative day and has returned to baseline levels in one case. Echocardiography showed mild, but significant, elevation of gradients in cryopreserved valves but none in the decellularized. CONCLUSIONS: Decellularized allografts had normal function up to 18 months and showed important reduction of the immunogenic response when compared to cryopreserved valves.  相似文献   
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Glucose is provided to cells by a family of glucose transport facilitators known as GLUTs. These transporters are expressed in a tissue specific manner and are overexpressed in many primary tumors of these tissues. Regulation of glucose transport facilitator expression has been demonstrated in endometrial tissue and endometrial adenocarcinoma. The following experiments were conducted to quantify and localize the expression of GLUT1 and GLUT8 in benign endometrium and compare this expression to endometrial cancer. Endometrial tissue samples were obtained from random hysterectomy specimens of patients with benign indications for surgery and endometrial cancer. Immunoblot and immunolocatization studies were performed using GLUT1 and GLUT8 specific antisera. Endometrial samples from 65 women who had undergone hysterectomy were examined (n=38 benign, n=27 malignant). A 44 and a 35.4 kDa immunoreacive species was demonstrated in endometrium and endometrial cancer for GLUT1 and GLUT8, respectively. Upregulation of GLUT1 expression was demonstrated with increasing grade of tumors (P<0.002). GLUT8 expression was increased in all tumor subtypes compared to atrophic endometrium (P<0.001). Apical localization by GLUT1 and GLUT8 was demonstrated in endometrial glands. GLUT1 and GLUT8 demonstrated diffuse intracellular localization in the cancer subtypes. GLUT1 and GLUT8 are expressed in both human endometrium and endometrial cancer. There appears to be a step-wise progression in GLUT1 and GLUT8 expression as tumor histopathology worsens. GLUT1 and GLUT8 may be important markers in tumor differentiation, as well as providing energy to rapidly dividing tumor cells.  相似文献   
19.
Objectives. Epididymal cystadenomas (ECs) are frequently found in association with von Hippel-Lindau disease (VHL), but little has been reported about their sonographic appearance. We review the sonographic appearance of ECs, the relationship of ECs to other manifestations of VHL, and the specific genetic mutations associated with ECs.Methods. Fifty-six male patients with VHL were examined with scrotal sonography and physical examination as part of a larger screening program for VHL. The head of the epididymis was measured in two planes on sonography and compared with age-matched normal controls. All VHL patients with palpable epididymal abnormalities or enlargement (more than two standard deviations) of the head of the epididymis on ultrasound were considered positive for EC.Results. Thirty of 56 (54%) male patients with VHL demonstrated a unilateral (n = 10; 33%) or bilateral (n = 20; 67%) solid abnormality in the head of the epididymis suggestive of EC. Sonographic appearances ranged from a solid mass with multiple tiny cysts to an almost completely solid mass. The most common appearance was a 15- to 20-mm solid mass with small cystic components. Dilated efferent ductules were seen within the testicle in 7 men, evidently a result of chronic obstruction. There was no association between the clinical subtype of VHL and the presence of ECs (P >0.10, chi square). Mutations resulting in a truncated gene product were associated with the development of ECs but the association did not reach statistical significance (P = 0.06).Conclusions. ECs are a common manifestation of VHL in men and exhibit a range of appearances on ultrasound. Sonography can be used to identify ECs and determine the extent of cystic dilation of the rete testes. The benign course of ECs and the usual absence of clinical symptoms favor a conservative approach to their management.  相似文献   
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