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Mehrany Khosrow MD Weenig Roger H. MD Pittelkow Mark R. MD Roenigk Randall K. MD Otley Clark C. MD 《Dermatologic surgery》2005,31(1):38-42
BACKGROUND: Cutaneous cancers exhibit a much higher incidence in patients with chronic lymphocytic leukemia than in nonleukemic patients. Squamous and basal cell carcinomas also exhibit greater subclinical tumor extension in patients with chronic lymphocytic leukemia. OBJECTIVE: The purpose of this study was to estimate and compare the recurrence rates of squamous cell carcinoma after Mohs' surgery in patients with chronic lymphocytic leukemia compared with those in controls and to evaluate differences among squamous cell carcinoma size and histologic grade. METHODS: We retrospectively assessed the clinical histories, postoperative notes, and surgical photographs of patients with chronic lymphocytic leukemia and controls matched (2:1) for age, sex, and surgical year. Both patients and controls underwent Mohs' surgery for squamous cell carcinoma of the head and neck at the Mayo Clinic between March 1988 and April 1999. RESULTS: Twenty-eight patients who underwent Mohs' surgery for 57 squamous cell carcinomas had 7 recurrences. The cumulative incidence of recurrence on a per-tumor basis was 4.3% at 1 year, 14.8% at 3 years, and 19.0% at 5 years. Squamous cell carcinoma was seven times more likely to recur in patients with chronic lymphocytic leukemia than in controls (p = .003). The distribution of tumor histologic grade was not significantly different between patients and controls (p = .39). Maximum preoperative tumor diameters were clinically similar between patients and controls (median 15 mm vs 14 mm; p = .04). CONCLUSION: The recurrence rates of squamous cell carcinoma were significantly higher in patients with chronic lymphocytic leukemia. Squamous cell carcinomas in patients with chronic lymphocytic leukemia did not exhibit a significant difference in histologic grade or clinical difference in preoperative tumor size. Close surveillance for squamous cell carcinoma recurrence is warranted in patients with chronic lymphocytic leukemia. 相似文献
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Holly L Rosenzweig Manabu Minami Nikola S Lessov Sarah C Coste Susan L Stevens David C Henshall Robert Meller Roger P Simon Mary P Stenzel-Poore 《Journal of cerebral blood flow and metabolism》2007,27(10):1663-1674
Lipopolysaccharide (LPS) preconditioning provides neuroprotection against subsequent cerebral ischemic injury. Tumor necrosis factor-alpha (TNFalpha) is protective in LPS-induced preconditioning yet exacerbates neuronal injury in ischemia. Here, we define dual roles of TNFalpha in LPS-induced ischemic tolerance in a murine model of stroke and in primary neuronal cultures in vitro, and show that the cytotoxic effects of TNFalpha are attenuated by LPS preconditioning. We show that LPS preconditioning significantly increases circulating levels of TNFalpha before middle cerebral artery occlusion in mice and show that TNFalpha is required to establish subsequent neuroprotection against ischemia, as mice lacking TNFalpha are not protected from ischemic injury by LPS preconditioning. After stroke, LPS preconditioned mice have a significant reduction in the levels of TNFalpha (approximately threefold) and the proximal TNFalpha signaling molecules, neuronal TNF-receptor 1 (TNFR1), and TNFR-associated death domain (TRADD). Soluble TNFR1 (s-TNFR1) levels were significantly increased after stroke in LPS-preconditioned mice (approximately 2.5-fold), which may neutralize the effect of TNFalpha and reduce TNFalpha-mediated injury in ischemia. Importantly, LPS-preconditioned mice show marked resistance to brain injury caused by intracerebral administration of exogenous TNFalpha after stroke. We establish an in vitro model of LPS preconditioning in primary cortical neuronal cultures and show that LPS preconditioning causes significant protection against injurious TNFalpha in the setting of ischemia. Our studies suggest that TNFalpha is a twin-edged sword in the setting of stroke: TNFalpha upregulation is needed to establish LPS-induced tolerance before ischemia, whereas suppression of TNFalpha signaling during ischemia confers neuroprotection after LPS preconditioning. 相似文献
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Anthony P. Khalifah Ramsey R. Hachem Murali M. Chakinala Roger D. Yusen Aviva Aloush G. Alexander Patterson Thalachallour Mohanakumar Elbert P. Trulock Michael J. Walter 《American journal of transplantation》2005,5(8):2022-2030
Bronchiolitis obliterans syndrome (BOS) is a major cause of lung allograft dysfunction. Although previous studies have identified mild to severe rejection (grade>or=A2) as a risk factor for BOS, the role of minimal rejection (grade A1) remains unclear. To determine if A1 rejection by itself is a risk factor for BOS, we performed a retrospective cohort study on 228 adult lung transplant recipients over a 7-year period. Cohorts were defined by their most severe rejection episode (none, A1 only, and >or=A2) and analyzed for the subsequent development and progression of BOS using univariate and multivariate time-dependent Cox regression analysis. In the univariate model, the occurrence of isolated minimal rejection was a risk factor for all stages of BOS. Similarly, multivariate models that included HLA mismatch, cytomegalovirus pneumonitis, community acquired viral infection, underlying disease and type of transplant demonstrated that A1 rejection was a distinct risk factor for BOS. Furthermore, the associated risk with A1 rejection was slightly greater than the risk from >or=A2 and treatment of A1 rejection decreased the risk for subsequent BOS stage 1. We conclude that minimal rejection is associated with an increased risk for BOS development and progression that is comparable to A2 rejection. 相似文献
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R. Brian Fazia Roger M. Mills C. Richard Conti Edward D. Staples 《Clinical cardiology》1996,19(8):672-674
Infective endocarditis is an infrequent but serious complication in heart transplant recipients. We report successful treatment for this serious complication. 相似文献