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21.
Since interleukin-2 (IL-2) and IL-4 act in concert to support the development of cytotoxic T lymphocytes (CTL) and the generation of antigen-specific tumour infiltrating lymphocytes (TIL), we investigated the interaction of these cytokines with an established TIL line. TIL proliferated in an additive fashion in response to suboptimal concentrations of IL-2 and various concentrations of IL-4. TIL possessed high-affinity IL-4 receptors whether cultured in recombinant IL-2 (rIL-2) or rIL-4, but cells cultured in rIL-2 had higher numbers of IL-4 receptors than cells cultured in rIL-4. When TIL were cultured in increasing concentrations of rIL-2, a dose-dependent enhancement in IL-4 receptor number was observed. The maximum induction of IL-4 receptor expression was achieved by 4 hr of incubation with rIL-2 and was completely blocked by cycloheximide. Other cytokines, such as rIL-1, recombinant tumour necrosis factor (rTNF), recombinant interferon-alpha (rIFN-alpha) and rIFN-gamma, had no effect on IL-4 receptor number. rIL-2 also up-regulated IL-4 receptors on CTLL-2, a murine CTL line. These data indicate that high-affinity IL-4 receptors exist on murine TIL and they can be up-regulated by IL-2. Our observation that IL-2 up-regulates IL-4 receptor may help explain the additive effects of these lymphokines on the proliferation of TIL and other cell lines. It may also help explain their co-operative effects on the generation of antigen-specific TIL and the differentiation of CTL. 相似文献
22.
Xu J Wang R Xie ZH Odero-Marah V Pathak S Multani A Chung LW Zhau HE 《The Prostate》2006,66(15):1664-1673
BACKGROUND: The ARCaP cell line was established from the ascites fluid of a patient with metastatic prostate cancer. This study characterized the host microenvironmental role in cancer progression, epithelial to mesenchymal transition (EMT), and bone and adrenal metastasis in parental ARCaP and its derived cell subclones. METHODS: Cytogenetic profiles, growth, migration, invasion, cellular interaction, drug sensitivities, and gene expression of ARCaP cell subclones were compared. In vivo gene expression, behavior, and metastasis of ARCaP subclones were analyzed by serial intracardiac injections into SCID mice. RESULTS: ARCaP(E) cells, with cobblestone morphology, underwent EMT through cellular interaction with host bone and adrenal gland. Lineage-derived ARCaP(M) cells, with spindle-shape fibroblastic morphology, exhibited decreased cell adhesion and increased metastasis to bone and adrenal gland. Cytogenetic analyses of parental and ARCaP subclones confirmed their clonality. CONCLUSIONS: ARCaP uniquely models the molecular basis of prostate cancer bone and adrenal metastases and epithelial to mesenchymal transition. 相似文献
23.
Cliff K. Watts David Jones Dee Crouch John Carter Leland Mew Barry Moseley 《The Physician and sportsmedicine》2013,41(3):99-104
In brief: To determine what public and individual efforts might reduce bicycling accidents and injuries, a survey was conducted during the primary cycling months (April through September) in Boulder, Colorado. Of 253 patients (87 women, 166 men, average age 22) treated for injuries in bicycling accidents, almost 30% of the accidents were caused by gravel, and nearly half involved a motor vehicle. The most frequent types of injury were abrasions, contusions, lacerations, and fractures. The survey results confirm the need for adequate head protection, satisfactory lighting, and increased awareness on the bicyclist's part. In addition, improved street maintenance will drastically reduce the number of cycling injuries and accidents. 相似文献
24.
Schiffmann R Hauer P Freeman B Ries M Scott LJ Polydefkis M Brady RO McArthur JC Wagner K 《Muscle & nerve》2006,34(1):53-56
We prospectively evaluated the effect of enzyme replacement therapy (ERT) on the intraepidermal nerve fiber density (IENFD) and thermal threshold in patients with Fabry disease, an X-linked disorder associated with a painful small-fiber neuropathy and decreased linear IENFD in a length-dependent pattern. Twenty-five hemizygous male patients with Fabry disease were enrolled in a 6-month, randomized, placebo-controlled ERT trial of 0.2 mg/kg of alpha-galactosidase A (agalsidase-alfa) every 2 weeks followed by an additional 12 months of open-label ERT for both populations. IENFD and thermal threshold were measured in the distal thigh at baseline, 6 months, and 18 months from initiation of the trial. We found no significant difference in IENFD between the treatment groups at 6 months. After an additional year of ERT, there was a significant reduction in IENFD in the patient group as a whole, attributable to the declining glomerular filtration rate. Thermal thresholds remained unchanged. We conclude that epidermal nerve fiber regeneration, as measured in the distal thigh, does not occur in this patient population after 12-18 months of ERT. 相似文献
25.
Helical structure and stability in human apolipoprotein A-I by hydrogen exchange and mass spectrometry 下载免费PDF全文
Palaniappan Sevugan Chetty Leland Mayne Sissel Lund-Katz David Stranz S. Walter Englander Michael C. Phillips 《Proceedings of the National Academy of Sciences of the United States of America》2009,106(45):19005-19010
Apolipoprotein A-I (apoA-I) stabilizes anti-atherogenic high density lipoprotein particles (HDL) in the circulation and governs their biogenesis, metabolism, and functional interactions. To decipher these important structure–function relationships, it will be necessary to understand the structure, stability, and plasticity of the apoA-I molecule. Biophysical studies show that lipid-free apoA-I contains a large amount of α-helical structure but the location of this structure and its properties are not established. We used hydrogen-deuterium exchange coupled with a fragmentation-separation method and mass spectrometric analysis to study human lipid-free apoA-I in its physiologically pertinent monomeric form. The acquisition of ≈100 overlapping peptide fragments that redundantly cover the 243-residue apoA-I polypeptide made it possible to define the positions and stabilities of helical segments and to draw inferences about their interactions and dynamic properties. Residues 7–44, 54–65, 70–78, 81–115, and 147–178 form α-helices, accounting for a helical content of 48 ± 3%, in agreement with circular dichroism measurements (49%). At 3 to 5 kcal/mol in free energy of stabilization, the helices are far more stable than could be achieved in isolation, indicating mutually stabilizing helix bundle interactions. However the helical structure is dynamic, unfolding and refolding in seconds, allowing facile apoA-I reorganization during HDL particle formation and remodeling. 相似文献
26.
Leland JY 《Clinics in Geriatric Medicine》2000,16(4):875-894
The culture of nursing homes historically has been rehabilitative. This approach has been enforced by the Omnibus Budget Reconciliation Act (1987) regulations, which focus on "decline" as largely avoidable. With the passage of the Prospective Payment System, nursing homes have become increasingly a site of death. In the same way that no sharp transition exists between living and dying, no sharp transition exists between life-prolonging, disease-specific therapy and palliative therapy. Life-prolonging therapy can lead to symptoms that require palliation, and, in some instances, (e.g., end-stage heart failure) life-prolonging therapy and palliative therapy may be indistinguishable. Palliative care, with the control of symptoms, relief of suffering, and promotion of quality of life, is appropriate to all stages of disease, with an increasing proportion of palliative care relative to curative therapy as the disease progresses. The goals of symptom management and attention to potential sources of suffering in palliative care are components of quality end-of-life care and are discussed. 相似文献
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Prolonged survival of patients receiving active immunotherapy with Canvaxin therapeutic polyvalent vaccine after complete resection of melanoma metastatic to regional lymph nodes 下载免费PDF全文
Morton DL Hsueh EC Essner R Foshag LJ O'Day SJ Bilchik A Gupta RK Hoon DS Ravindranath M Nizze JA Gammon G Wanek LA Wang HJ Elashoff RM 《Annals of surgery》2002,236(4):438-449
OBJECTIVE: To determine whether adjuvant postoperative active specific immunotherapy with a therapeutic polyvalent vaccine (PV) called Canvaxin can prolong survival following complete resection of melanoma metastatic to regional nodes (American Joint Committee on Cancer [AJCC] stage III melanoma). SUMMARY BACKGROUND DATA: Despite complete lymphadenectomy, 5-year overall survival (OS) for patients with melanoma metastatic to regional lymph nodes is only 20% to 50%, depending on the number of tumor-involved nodes. In 1984, the authors began phase II trials of Canvaxin PV as postsurgical adjuvant therapy for AJCC stage III melanoma. METHODS: Patients who received PV between 1984 and 1998 were compared with patients who did not receive PV postsurgical therapy between 1971 and 1998. The seven covariates recently defined by the AJCC Melanoma Staging Committee (number of metastatic nodes, palpable status, ulceration, age, primary site, pT stage, and gender) were included by Cox regression in a multivariate model of OS. A computerized program matched PV and non-PV patients by these covariates. RESULTS: Of 2,602 patients who underwent complete lymphadenectomy for AJCC stage III melanoma with regional nodal metastases and were followed up by the same team of oncologists between 1971 and 1998, 935 received PV and 1,667 did not. Median OS and 5-year OS were significantly higher in PV than non-PV patients (56.4 vs. 31.9 months and 49% vs. 37%, respectively; P =.0001). When the non-PV patients were matched by the four most significant covariates, 447 matched pairs were formed between patients seen before or after January 1, 1985, and the OS was not different between the two time periods ( P=.789). However, when the PV patients were matched with non-PV patients by six covariates forming 739 pairs, the PV patients survived longer ( P=.0001). Detailed analysis of the 1,505 patients who were seen or who began vaccine therapy within 4 months after lymphadenectomy, and who had more complete data on the seven prognostic covariates showed that median OS and 5-year OS were higher in 445 PV patients than in 1,060 non-PV patients: 70.4 versus 31 months and 52% versus 37%, respectively (P =.0001). Multivariate Cox regression analysis identified six significant prognostic factors: number of metastatic nodes, size of metastatic nodes, pT stage, ulceration, age, and PV therapy. PV therapy reduced the relative risk of death to 0.64 (95% confidence interval, 0.55-0.76) ( P=.0001); sex and site of primary were of borderline significance. CONCLUSIONS: This large single-institution study independently confirmed the significance of prognostic covariates in the new AJCC staging system. By using modern statistical methods that controlled for all known prognostic factors, it also demonstrated PV's ability to significantly enhance OS. A multicenter phase III randomized trial is underway to validate the efficacy of PV as a postsurgical adjuvant. 相似文献
30.
Background We have observed prolonged survival in patients undergoing vaccine reinduction after resection of recurrent metastatic melanoma
and adjuvant polyvalent allogenic cell vaccine (PACV) immunotherapy. We hypothesized that reinduction with a more intensive
vaccine regimen would re-stimulate specific immune responses that were correlated with survival after recurrence.
Methods From 1996 to 1998, 194 patients developed recurrence during adjuvant PACV (CancerVax vaccine) treatment after resection of
metastatic melanoma. Recurrent disease was treated with or without vaccine reinduction. Reinduction regimen entailed an increased
vaccine frequency and coadministration of two doses of bacille Calmette-Guérin (BCG). PACV Delayedtype hypersensitivity (DTH)
responses were prospectively recorded. Survival was defined as the interval from recurrence to death.
Results Ninety-four patients underwent reinduction immunotherapy. DTH responses to PACV before recurrence increased significantly
after reinduction therapy (P=.0001). The median survival time was 37 months for reinduced patients and 17 months for other patients. On multivariate analysis,
reinduction status remained a significant prognostic variable (P=.0277). In the reinduction group, there was a significant correlation between PACV DTH responses and survival (P=.0178).
Conclusions Reinduction vaccine regimen can enhance immune responses in previously immunized patients and is associated with prolonged
survival after recurrence in patients receiving the same active specific immunotherapy.
Presented at the Society of Surgical Oncology annual meeting. Washington, DC, March 15–18, 2001. 相似文献