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51.
The management of rheumatoid arthritis (RA) with biological response modifiers (BRMs) is reviewed. RA, an autoimmune disorder affecting 1-2% of the world's population, is characterized by inflammation of synovial tissues, joint swelling, stiffness, and pain that may progress to joint erosion. There is strong evidence that inflammatory mediators, such as tissue necrosis factor-alpha (TNF-alpha) and interleukin-1 (IL-1), play a critical role in the pathogenesis of this disorder. IL-1-receptor antagonist (IL-1Ra) is produced in healthy subjects and helps to protect against the adverse effects associated with IL-1 overexpression. Administration of IL-1Ra or similar agents may reduce the effects of IL-1 and ameliorate inflammatory conditions. Traditional treatment of RA has been based on symptomatic management with non-steroidal antiinflammatory drugs, disease-modifying antirheumatic drugs, and corticosteroids, each of which has substantial drawbacks in terms of effectiveness or adverse effects. Newer therapeutic strategies for blocking the biological effects of inflammatory cytokines include antibodies directed against TNF (e.g., infliximab), soluble receptors (e.g., etanercept) and receptor antagonists to IL-1 (anakinra) [corrected]. Clinical trials indicate that these BRMs may be more effective than traditional agents because they are able to alter joint remodeling in addition to attenuating symptoms. Anti-TNF therapies may be associated with increased risk for infections, sepsis, tuberculosis reactivation, demyelination disorders, and blood dyscrasias; anakinra appears to be safer. Combination therapy with BRMs may be more appropriate for RA than monotherapy. The role of BRMs in the treatment of RA will evolve as investigators learn more about the drugs and the disorder. 相似文献
52.
The Notch family of transmembrane receptors has been implicated in the regulation of many developmental processes. In this study, we evaluated the role of Notch4 in immature hematopoietic progenitors by inducing, with retroviral transduction, enforced expression of Int-3, the oncogenic and constitutively active form of mouse Notch4. Int-3-transduced human myeloid leukemia (HL-60) cells demonstrated significantly delayed expression of differentiation markers following retinoic acid and 12-0-tetradecanoylphorbol 13-acetate treatment. Furthermore, HL-60 cells expressing Int-3 displayed a slower growth rate than cells infected with void virus, and accumulation in the G0/G1 phases of cell cycle. Transduction with deletion mutants of Int-3 defined the importance of individual domains of the protein (in particular, the ANK domain and the C-terminal domain) in the inhibition of differentiation and growth arrest of HL-60 cells. When mouse bone marrow enriched for stem cells (5-fluorouracil-resistant, lineage negative) was transduced and cultured for two weeks, the Int-3-transduced population displayed a lower expression of differentiation markers and a three- to five-fold higher frequency of colony-forming cells (CFU-GM/BFU-E) than control cultures. These results strongly support the notion that Notch signaling inhibits differentiation and promotes expansion of hematopoietic stem/progenitor cells. 相似文献
53.
Intracerebral clysis in a rat glioma model 总被引:4,自引:0,他引:4
Bruce JN Falavigna A Johnson JP Hall JS Birch BD Yoon JT Wu EX Fine RL Parsa AT 《Neurosurgery》2000,46(3):683-691
OBJECTIVE: Intracerebral clysis (ICC) is a new term we use to describe convection-enhanced microinfusion into the brain. This study establishes baseline parameters for preclinical, in vivo, drug investigations using ICC in a rat glioma model. METHODS: Intracranial pressure was measured, with an intraparenchymal fiber-optic catheter, in male Fischer rats 10, 15, 20, and 25 days after implantation of C6 glioma cells in the right frontal lobe (n = 80) and in control rats without tumor (n = 20), before and during ICC. A 25% albumin solution (100 microl) was infused through an intratumoral catheter at 0.5, 1.0, 2.0, 3.0, and 4.0 microl/min. Infusate distribution was assessed by infusion of fluorescein isothiocyanate-dextran (Mr 20,000), using the aforementioned parameters (n = 36). Brains were sectioned and photographed under ultraviolet light, and distribution was calculated by computer analysis (NIH Image for Macintosh). Safe effective drug distribution was demonstrated by measuring tumor sizes and apoptosis in animals treated with N,N'-bis(2-chloroethyl)-N-nitrosourea via ICC, compared with untreated controls. Magnetic resonance imaging noninvasively confirmed tumor growth before treatment. RESULTS: Intracranial pressure increased with tumor progression, from 5.5 mm Hg at baseline to 12.95 mm Hg on Day 25 after tumor cell implantation. Intracranial pressure during ICC ranged from 5 to 21 mm Hg and was correlated with increasing infusion volumes and increasing rates of infusion. No toxicity was observed, except at the higher ends of the tumor size and volume ranges. Fluorescein isothiocyanate-dextran distribution was greater with larger infusion volumes (30 microl versus 10 microl, n = 8, P < 0.05). No significant differences in distribution were observed when different infusion rates were compared while the volume was kept constant. At tolerated flow rates, the volumes of distribution were sufficient to promote adequate drug delivery to tumors. N,N'-Bis(2-chloroethyl)-N-nitrosourea treatment resulted in significant decreases in tumor size, compared with untreated controls. CONCLUSION: The C6 glioma model can be easily modified to study aspects of interstitial delivery via ICC and the application of ICC to the screening of potential antitumor agents for safety and efficacy. 相似文献
54.
Robert L. Harris MD Geoffrey W. Cundiff MD James P. Theofrastous MD Haewon Yoon MD Richard C. Bump MD W.Allen Addison MD 《American journal of obstetrics and gynecology》1997,177(6):1367-1371
OBJECTIVE: Our goal was to evaluate the role of intraoperative cystoscopy during surgery for pelvic organ prolapse and urinary incontinence. STUDY DESIGN: Charts of 224 consecutive patients who had intraoperative cystoscopy performed after urogynecologic surgery were reviewed. RESULTS: Nine injuries occurred that were unsuspected before cystoscopy, for an incidence of 4%. Six ureteral ligations occurred, four after Burch cystourethropexy and two after vaginal culdoplasty. Intravesical sutures were noted after two Burch procedures, and another injury occurred with passage of fascia lata through the bladder during a pubovaginal sling procedure. Eight injuries were managed by removal and replacement of the suture or sling with only one requiring ureteroneocystotomy. When patients with injuries were compared with those without, there were no statistical differences in demographic or surgical parameters. CONCLUSIONS: The potential for damage to the lower urinary tract is significant with complex urogynecologic surgery. Because of the increased and delayed morbidity associated with unrecognized injury, intraoperative surveillance cystoscopy should be considered a part of all such procedures.(Am J Obstet Gynecol 1997;177:71) 相似文献
55.
Yoon KH Ha HK Kim CG Roh BS Yun KJ Chae KM Lim JH Auh YH 《AJR. American journal of roentgenology》2000,175(4):1135-1139
OBJECTIVE. We describe the CT and pathologic features of malignant papillary neoplasms of the intrahepatic bile ducts in 15 patients. CONCLUSION. CT is a useful technique for revealing intraductal lesions, although the findings are nonspecific and variable. When intraductal masses or nodules are seen with localized dilatation of the intrahepatic bile ducts on CT scans, malignant papillary neoplasms of the intrahepatic bile ducts should be included in the differential diagnosis. 相似文献
56.
57.
Invasive middle ear cholesterol granuloma involving the basal turn of the cochlea with profound sensorineural hearing loss. 总被引:1,自引:0,他引:1
STUDY DESIGN: A retrospective surgical case review. SETTING: A tertiary-care, university teaching hospital. PATIENTS: The authors describe a unique case operated on for a middle ear cholesterol granuloma, which had invaded the cochlea and vestibule causing profound sensorineural deafness. INTERVENTIONS: Extended radical mastoidectomy and labyrinthectomy with musculofascial seal. RESULTS: Successful postoperative outcome with no recurrence seen after 2 years of follow up. CONCLUSION: To the authors' knowledge, this is the first reported case of a primary middle ear cholesterol granuloma with direct invasion into the cochlea. Such invasion of the otic capsule by cholesterol granulomas is rare and presents a diagnostic challenge to the attending otologist and radiologist. Salient points of the case history, pathogenesis, imaging studies, histopathology, and management are presented with a review of the current literature. 相似文献
58.
Myositis ossificans originating from the chest wall is extremely rare. We report a case of myositis ossificans occurring in a young woman with progressive painful swelling in the chest wall. Preoperative examination suggested a malignant neoplasm originating from soft tissue. Although rare, myositis ossificans is one of the potential causes of painful swelling in the chest wall, and can be mistaken for a malignant neoplasm. 相似文献
59.
60.
Maria V Nesterova Natalie R Johnson Trina Stewart Scott Abrams Yoon S Cho-Chung 《Clinical cancer research》2005,11(16):5950-5955