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Direct demonstration that autologous bone marrow transplantation for solid tumors can return a multiplicity of tumorigenic cells 总被引:5,自引:2,他引:5
Rill DR; Santana VM; Roberts WM; Nilson T; Bowman LC; Krance RA; Heslop HE; Moen RC; Ihle JN; Brenner MK 《Blood》1994,84(2):380-383
Patients with solid tumors are increasingly being treated by autologous bone marrow transplantation (BMT). Although response rates appear to be increased, disease recurrence is the commonest cause of treatment failure. Whether relapse is entirely due to residual disease in the patient or arises also from infiltrating malignant cells contained in the autologous marrow transplant has not been resolved. If the latter explanation is correct, then purging would be required as part of the transplantation procedure. We used retrovirally mediated transfer of the neomycin-resistance gene to mark BM harvested from eight patients with neuroblastoma in clinical remission. The marked marrow cells were subsequently reinfused as part of an autologous BMT. At relapse, we sought the marker gene in malignant cell populations. Three patients have relapsed, and in each the marker gene was detected by phenotypic and genetic analyses of resurgent malignant cells at medullary and extramedullary sites. Analysis of neuroblast DNA for discrete marker gene integration sites suggested that at least 200 malignant cells, each capable of tumor formation, were introduced with the autologous marrow transplant and contributed to relapse. Thus, autologous BMTs administered to patients with this solid tumor may contain a multiplicity of malignant cells that subsequently contribute to relapse. The marker-gene technique we describe should permit evaluation of the mechanisms of relapse and the efficacy of purging in patients receiving autologous marrow transplantation for other solid tumors that infiltrate the marrow. 相似文献
74.
Background
Suicide is a leading cause of death, particularly among young adults. The rapid growth of social media and its heavy use by young adults presents new challenges and opportunities for suicide prevention. Social media sites are commonly used for communicating about suicide-related behavior with others, which raises the possibility of using social media to help prevent suicide. However, the use of social media varies widely between different suicide prevention advocates. The role this type of intervention should play in a community’s overall suicide prevention strategy remains a matter of debate.Aim
Explore the ways in which stakeholders use social media for suicide prevention and assess their views about the potential utility of social media as a suicide prevention tool.Methods
A 12-week stakeholder consultation that involved the online administration and completion of surveys by 10 individuals who conduct research about suicide and social media, 13 organizations that use social media for suicide prevention purposes, and 64 users of social media.Results
Social media was seen as a useful means of delivering a range of suicide prevention activities. Respondents reported that the key benefits of social media were the opportunity to obtain emotional support from others, to express one’s feelings, to talk to others with similar problems, and to provide help to others. The social media site believed to hold most potential for delivering suicide prevention activities was Facebook. There were concerns about potential risks of social media, but respondents felt the potential benefits outweighed the risks.Conclusions
Social media was recognized by different types of stakeholders as holding potential for delivering suicide prevention activities. More research is required to establish the efficacy and safety of potential social media-based interventions and ethical standards and protocols to ensure that such interventions are delivered safely need to be developed and implemented. 相似文献75.
76.
Ultrasound‐guided percutaneous tenotomy for the treatment of iliopsoas impingement: A description of technique and case study 下载免费PDF全文
Matthew J Sampson Nimah Rezaian James MK Hopkins 《Journal of Medical Imaging and Radiation Oncology》2015,59(2):195-199
Iliopsoas impingement is a commonly recognised source of groin pain following total hip replacement. When conservative measures fail, open or arthroscopic iliopsoas tendon release can reliably alleviate pain and improve function. This article describes an alternative ultrasound‐guided percutaneous technique, achieving iliopsoas tenotomy utilising a modified 18G coaxial needle and thus minimising the morbidity and cost associated with an open or arthroscopic procedure. This method proved successful with resultant complete resolution of patient symptoms. To the knowledge of the authors, this is the first case of ultrasound‐guided percutaneous iliopsoas tenotomy for iliopsoas impingement post total hip replacement. 相似文献
77.
5-羟色胺对气道平滑肌细胞增生的影响及c-fos的表达 总被引:7,自引:0,他引:7
5-羟色胺对气道平滑肌细胞增生的影响及c-fos的表达刘振千梁凤珍马军红戚好文为了探讨哮喘气道平滑肌层增厚的机制,考察哮喘的炎性介质5-羟色胺(5-HT)对兔气道平滑肌细胞(ASMC)增生的影响及原癌基因c-fos的表达。新西兰大白兔,抗α-肌动蛋白... 相似文献
78.
RENEE A. GLOVER CYNTHIA S. BAILEY KIM E. BARRETT S.I. WASSERMAN IRMA GIGLI 《The British journal of dermatology》1990,122(4):501-512
We report that protoporphyrin (PP) and ultraviolet light (UVA) induces histamine release from rat peritoneal mast cells, mouse bone marrow mast cells and human cutaneous mast cells in a dose- and temperature-dependent manner. The mast-cell activation was associated with loss of membrane integrity and inhibited by the hydrogen peroxide scavenger, catalase. Histamine release was independent of extracellular calcium in the rodent mast cells, but was markedly reduced in the absence of calcium in human cells. These findings indicate that PP and UVA induce mast-cell-mediator release by a process that may involve hydrogen peroxide formation. There appear to be differences in response to PP and UVA between rodent and human mast cells. 相似文献
79.
Deposition of autofluorescent eosinophil granules in pathologic bone marrow biopsies 总被引:2,自引:0,他引:2
Eosinophil granules are intensely autofluorescent when excited by green light. To determine if eosinophils degranulate in the bone marrows of patients with a variety of diseases, we used green light epifluorescence microscopy to examine deparaffinized and dezenkerized sections of 49 bone marrow core biopsies. In 14 of the biopsies, there was striking extracellular deposition of intensely autofluorescent eosinophil granules in addition to numerous intact eosinophils. Among the 14 specimens with extracellular autofluorescence were seven cases of leukemia, four cases of non-Hodgkin's lymphoma, two cases of myelofibrosis, and one case of pancytopenia with eosinophilia. In the remaining 35 specimens, only intact eosinophils were identifiable. There was no extracellular autofluorescence in three normal marrows, four marrows from AIDS patients, or three biopsies from patients with idiopathic thrombocytopenic purpura (ITP). We conclude that green light epifluorescence microscopy identifies extracellular deposits of eosinophil granules in bone marrow biopsies of some neoplastic disorders and in diseases associated with reticulin fibrosis. 相似文献
80.