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RK Batra JC Olsen DK Hoganson B Caterson RC Boucher 《Canadian Metallurgical Quarterly》1997,272(18):11736-11743
Gene therapy may be an important adjuvant for treating cancer in the pleural space. The initial results of retroviral gene transfer to cancer cells in malignant pleural effusions revealed that transduction was markedly inhibited, and studies to characterize the inhibitory factor(s) were performed. The inhibition was contained within the soluble, rather than cellular, components of the effusions and was demonstrated with amphotropic, gibbon ape leukemia virus, and vesicular stomatitis virus-glycoprotein pseudotyped retroviral vectors. After excluding complement proteins, a series of studies identified chondroitin sulfates (CSs) as the inhibitory substances. First, treatment of the effusions with mammalian hyaluronidase or chondroitinases, but not Streptomyces hyaluronidase, abolished the inhibitory activity. Second, addition of exogenous CS glycosaminoglycans mimicked the inhibition observed with pleural effusions. Third, immunoassays and biochemical analyses of malignant pleural effusion specimens revealed CS in relevant concentrations within pleural fluid. Fourth, proteoglycans/glycosaminoglycans isolated from the effusions inhibited retroviral gene transfer. Analyses of the mechanism of inhibition indicate that the chondroitin sulfates interact with vector in solution rather than at the target cell surface. These results suggest that drainage of the malignant pleural effusion, and perhaps enzymatic pretreatment of the pleural cavity, will be necessary for efficient retroviral vector mediated gene delivery to pleural metastases. 相似文献
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STUDY DESIGN: The study of two patients whose rib deformity was treated using a new endoscopic thoracoplasty technique is reported. OBJECTIVES: To report a new endoscopic thoracoplasty technique for the treatment of rib deformities associated with idiopathic scoliosis. SUMMARY OF BACKGROUND DATA: Thoracoplasty has traditionally been performed as an open procedure, often necessitating additional incisions and/or tissue dissection. METHODS: Two children with significant rib humps associated with idiopathic scoliosis were treated with a new endoscopic thoracoplasty technique. RESULTS: Both children showed dramatic cosmetic improvement of their rib deformity. CONCLUSIONS: The indications for the use of video-assisted thoracoscopic surgery in the treatment of pediatric spinal deformity are expanding. We have extended our video-assisted thoracoscopic surgery repertoire to include endoscopic thoracoplasty for treatment of rib deformities associated with idiopathic scoliosis. The technique for endoscopic thoracoplasty is discussed, and illustrative cases are presented. 相似文献
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RK Manoff 《Canadian Metallurgical Quarterly》1997,57(3):260-265
The possible contamination of groundwater by the insecticide carbofuran was assessed with the behavior assessment model (BAM) and groundwater pollution-potential model (GWP). Dissipation coefficients of this insecticide in two subtropical soils at different moisture contents and soil temperatures were studied by determining the degradation and adsorption of the herbicide in soils. Movement of carbofuran was studied by leaching the insecticide in a soil column in the laboratory. Under 40% field capacity and at 25 degrees C, more than 80% of carbofuran residue was found in both Luchu clay and Yuanlin silty clay loam after incubation for 63 days. The results indicate that the higher the moisture content in the soil, the less the carbofuran residue under the soil moisture below the field capacity. Carbofuran tends to dissipate more easily in Yuanlin soil than in Luchu soil. The distribution coefficient (Kd) with r2 of 0.69 and 0.92 for Luchu and Yuanlin soils, respectively, was found using the first-order kinetics law. In leaching experiment, carbofuran exhibited easier movement in Luchu than in Yuanlin soil. 相似文献
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RK Ganju WC Hatch H Avraham MA Ona B Druker S Avraham JE Groopman 《Canadian Metallurgical Quarterly》1997,185(6):1055-1063
The related adhesion focal tyrosine kinase (RAFTK), a recently discovered member of the focal adhesion kinase family, has previously been reported to participate in signal transduction in neuronal cells, megakaryocytes, and B lymphocytes. We have found that RAFTK is constitutively expressed in human T cells and is rapidly phosphorylated upon the activation of the T cell receptor (TCR). This activation also results in an increase in the autophosphorylation and kinase activity of RAFTK. After its stimulation, there was an increase in the association of the src cytoplasmic tyrosine kinase Fyn and the adapter protein Grb2. This association was mediated through the SH2 domains of Fyn and Grb2. RAFTK also co-immunoprecipitates with the SH2 domain of Lck and with the cytoskeletal protein paxillin through its COOH-terminal proline-rich domain. The tyrosine phosphorylation of RAFTK after T cell receptor-mediated stimulation was reduced by the pretreatment of cells with cytochalasin D, suggesting the role of the cytoskeleton in this process. These observations indicate that RAFTK participates in T cell receptor signaling and may act to link signals from the cell surface to the cytoskeleton and thereby affect the host immune response. 相似文献
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Although rare, drug abuse problems present a complex set of physical and psychosocial issues that complicate cancer treatment and pain/ symptom management. Most oncologists are not be well versed in either the conceptual or practical issues related to addiction. As a result, they often struggle in their attempts to effectively treat patients who are or have been substance abusers, and they find it difficult to understand issues of addiction in patients with pain who have no history of substance abuse. In the first installment of a two-part series, the authors explore the epidemiology of substance abuse. An examination of the distinctions between abuse and dependence leads to definitions of these terms appropriate for the oncology setting. Guidelines for assessing aberrant drug-taking behavior are also offered. Part 2, which will appear in the next issue of ONCOLOGY, will discuss the clinical management of cancer patients with a history of substance abuse. 相似文献
30.
JL Vallet RK Christenson WE Trout HG Klemcke 《Canadian Metallurgical Quarterly》1998,76(10):2657-2670
This experiment consisted of the following treatment-breed groups: 1) White crossbred gilts, 2) White crossbred gilts treated with progesterone (200 mg/d in corn oil given on d 2 and 3 after estrus), and 3) Chinese Meishan gilts. Pregnant and nonpregnant gilts (n=3 to 6) from each treatment-breed combination were assigned to be slaughtered on d 10, 11, 12, 13, and 15. At slaughter each uterine horn was flushed with 20 mL of minimal essential medium. Uterine flushings were assayed for total protein, acid phosphatase, uteroferrin, retinol-binding protein, and oxytocin. Uterine flush total protein was increased by progesterone treatment, was unaffected by pregnancy status, and was less in Meishans. Similar patterns were found for retinol binding protein and uteroferrin, except that uteroferrin was greater in pregnant than in nonpregnant gilts. Oxytocin was greater in pregnant than in nonpregnant gilts, was not influenced by progesterone treatment, and was similar in Meishan and in White crossbred gilts. These results indicate that the conceptus does not influence secretion of either total protein or retinol binding protein during pregnancy and that the onset of secretion of these uterine proteins may be controlled by progesterone. The presence of the conceptus is associated with increased uteroferrin and oxytocin production. The decreased secretion of uterine proteins in Meishan gilts may partially explain the slower embryonic development that has been reported for this breed. 相似文献