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91.
Anne M Lewis Sheelu Varghese Hui Xu H Richard Alexander 《Journal of translational medicine》2006,4(1):48
The tumor microenvironment consists of tumor, immune, stromal, and inflammatory cells which produce cytokines, growth factors,
and adhesion molecules that promote tumor progression and metastasis. Of particular interest in this setting is interleukin-1
(IL-1), a pleiotropic cytokine with numerous roles in both physiological and pathological states. It is known to be up regulated
in many tumor types and has been implicated as a factor in tumor progression via the expression of metastatic and angiogenic
genes and growth factors. A number of studies have reported that high IL-1 concentrations within the tumor microenvironment
are associated with a more virulent tumor phenotype. Solid tumors in which IL-1 has been shown to be up regulated include
breast, colon, lung, head and neck cancers, and melanomas, and patients with IL-1 producing tumors have generally bad prognoses.
The exact mechanisms by which IL-1 promotes tumor growth remain unclear, though the protein is believed to act via induction
of pro-metastatic genes such as matrix metalloproteinases and through the stimulation of adjacent cells to produce angiogenic
proteins and growth factors such as VEGF, IL-8, IL-6, TNFα, and TGFβ. The IL-1 receptor antagonist (IL-1ra) is a naturally
occurring inhibitor to IL-1 and acts by binding to the IL-1 receptor without activating it. The protein has been shown to
decrease tumor growth, angiogenesis, and metastases in murine xenograft models. Our focus in this review is to summarize the
known data on the role of IL-1 in tumor progression and metastasis and the use of IL-1 inhibition as a novel therapeutic approach
in the treatment of solid organ malignancies. 相似文献
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Abstract
Background: In recent years, biomaterials are being found and frequently utilized in bone defects. They have also gained significant precedence
in hand surgery.
Objectives: The respective requirements for such replacement material will be cited and acknowledged in this article. The individual material
groups will also be referred to in this review. An introduction to some of the customary bone replacement materials will be
cited and concluded with a corresponding recommendation.
Conclusion: The implantation of autologous cancellous bone is still regarded today as the “gold standard”. Nevertheless, the usage of
bone replacement material can be an enormous advantage in certain indications.
The original article can be found online at
There was an error in the author’s affiliation and the address for correspondence was incomplete. Please note the correct
institution and complete address:
Department of Orthopedics and Traumatology, Hand-, Foot- and Reconstructive Surgery, Kreiskrankenhaus Gummersbach GmbH, Germany.
Alexander von Friesen, MD Department of Orthopedics and Traumatology, Hand-, Foot- and Reconstructive Surgery Kreiskrankenhaus
Gummersbach GmbH Wilhelm-Breckow-Allee 20 51643 Gummersbach Germany Phone (+49/2261) 171-575, Fax -449 e-mail: Friesen@kkh-gummersbach.de 相似文献
96.
97.
Successful treatment of posttraumatic chronic osteitis is often only achieved at the cost of some degree of bone loss. Various procedures for segmental transfer based on Ilizarov’s callus distraction technique have become established for reconstruction of extensive bony substance defects in recent years. Technically, both extramedullary and intramedullary procedures are available for the achievement of such a segmental transfer. Various factors must be taken into account when it is necessary to decide whether segmental transfer by means of a ring fixator, a unilateral fixateur externe or an intramedullary force carrier in combination with a fixateur externe or tension wires as the transfer system is indicated. These include how long the history of osteitis already is, how extensive it is, time taken for successful treatment of infection, soft tissue situation, resulting length of the defect following resection, and the patient’s age, together whether there are any patient-specific risk factors or comorbidities. In this paper an algorithm for deciding on the specific situations in which the different techniques of segmental transfer are indicated is discussed on the basis of many years of clinical experience in postinfectious defects on the lower extremities. 相似文献
98.
99.
Fifty patients underwent chemonucleolysis for the treatment of lumbar disk herniations unresponsive to conservative therapy. In patients treated with chymopapain, unrelieved sciatica was the most common cause of clinical treatment failure. Eight patients (16%) experienced no relief or only a transient reduction in their radicular symptoms following chymopapain injection. All eight patients were clinically reevaluated and underwent repeat neuroradiographic studies. Computed axial tomography and lumbar myelography demonstrated persistent nerve root compromise at the level of the injected disk space. Open diskectomy was performed in all eight cases. Postoperatively, seven patients noted complete resolution of their radicular symptoms; one patient had intermittent low back and leg pain following surgery. 相似文献
100.
Development of cholinergic retinal neurons from embryonic chicken in monolayer cultures: stimulation by glial cell-derived factors 总被引:3,自引:0,他引:3
H D Hofmann 《The Journal of neuroscience》1988,8(4):1361-1369
In recent years evidence has indicated that, like the PNS, the development of the CNS is influenced by neuronotrophic polypeptide factors. In the present study, cultures of dissociated retinal neurons from 8-d-old chicken embryos were used to investigate the role of neuronotrophic factors (NTF) in the development of the neural retina. CAT, which in vivo is located in amacrine cells of the retina, served as a marker for studying the in vitro development of cholinergic retinal neurons. Differentiation of cholinergic cells under control conditions was indicated by a 10-fold increase of enzyme activity during a 7-d culture period. Addition of media conditioned by high-density retinal cultures resulted in a further stimulation of CAT activity by 100-400%. The CAT-stimulating activity was associated with a high-molecular-weight component of the retina conditioned medium (RCM) and was sensitive to protease treatment, but was not affected by other hydrolytic enzymes. The putative cholinergic factor was secreted by retinal cultures virtually free of neurons, suggesting that it is mainly produced by Müller cells. CAT-stimulating activity was also present in extracts from embryonic chicken retinae and medium conditioned by rat retinal cultures. NGF, anti-NGF antiserum, extracts from chicken brain tissues, and a number of other extracts and conditioned media, all known to contain neuronotrophic activities, were found to have no influence on cholinergic development in chicken retinal cultures. An extract from non-retinal eye tissue containing ciliary neuronotrophic factor (CNTF) stimulated CAT activity to the same extent as did RCM.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献