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61.
Skp2 protein expression in soft tissue sarcomas.   总被引:15,自引:0,他引:15  
BACKGROUND: p45 S phase kinase-associated protein-2 (p45(skp2)), a member of the F-box family of proteins, is an important component of the Skp1-Cullin-F-box protein (SCF) ubiquitin-ligase complex (SCF(skp2)). The latter has been implicated in the ubiquitination and degradation of p27(kip1) (p27) and G(1)-S cell cycle progression. The expression and prognostic role of Skp2 in a large series of soft tissue sarcomas has not been previously investigated. METHODS: Clinicopathologic features and immunohistochemical expression of Skp2, p27, and Ki-67 proteins were studied in 182 cases of soft tissue sarcomas (American Joint Committee on Cancer stages II and III). Survival analyses were performed using the Kaplan-Meier method and the Cox regression model. RESULTS: The male to female ratio was 1.2:1, and the median age at the diagnosis was 53 years. The tumors were predominantly located in the lower extremities (n = 163; 90%) and had a median size of 9 cm. High Skp2 expression (> or = 10% of the cells) was identified in 68 tumors (37%), and was correlated with high grade histology (P =.002) and Ki-67 proliferative index (r = 0.44; P <.0001), but not with p27 expression (r = -0.02; P =.80). By univariate analysis, high Skp2 expression was associated with decreased metastasis-free, disease-free, and overall survival. In a multivariate model, high Skp2 expression was an independent predictor for decreased local recurrence-free, disease-free, and overall survival. CONCLUSION: These results indicate that Skp2 expression is associated with cell proliferation and a worse prognosis in soft tissue sarcomas. The lack of an inverse correlation between Skp2 and p27 suggests that additional molecular events associated with either Skp2 expression or p27 proteolysis may be operating in these tumors.  相似文献   
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To assess the role of adjuvant therapy in the treatment of osteogenic sarcoma of the head and neck, treatment and survival information from 173 patients with osteosarcoma of the head and neck was entered into a database. A meta-analysis of the data was attempted with primary emphasis on the effect of adjuvant therapy on disease outcome. The overall 5-year survival was 37%. Patients with mandibular and maxillary tumors had similar survival rates; both groups fared significantly better than patients with extragnathic tumors (P<0.001). Treatment with surgery alone was associated with significantly longer survival rates (P<0.03) than surgery with adjuvant therapy. In the majority of patients reported, information about surgical margins was not available. For this reason, the differences may not adequately represent the effect of adjuvant therapy. While there have been encouraging results with adjuvant treatment protocols for long bone osteosarcoma, the ultimate role of radiation and chemotherapy in the management of osteosarcoma of the head and neck remains unproven. Nevertheless, we recommend that adjuvant therapy be considered due to the poor prognosis in osteosarcoma of the head and neck.  相似文献   
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OBJECTIVE: This paper presents our experience with gunshot wounds to the temporal bone and discusses facial nerve lesions, surgical indication, surgical timing, and other findings. STUDY DESIGN: We performed a retrospective review of patients treated for facial nerve lesion after gunshot injury to the temporal bone. SETTING: The study was performed in the Otolaryngology Department of the University of Sao Paulo Medical School, Sao Paulo, Brazil. PATIENTS: Ninety-eight patients treated between 1988 and 1999 were analyzed. INTERVENTION: Facial nerve lesions, bullet locations, and surgical techniques were analyzed. Patients were monitored for 2 years. RESULTS: Gunshot trauma to the temporal bone presented considerable tissue loss resulting from the abrasion effect and severity of the impact. The third segment of the facial nerve was most affected, and the bullet was typically found lodged in the mastoid tip. Postoperative infection was common. Such cases required revision surgery, resulting in worse cosmetic outcomes than in cases of closed trauma. CONCLUSIONS: Surgical exploration of the facial nerve should be performed as soon as possible, since long delays increase the chance of traumatic neuroma and more pronounced scarring around the facial nerve. Open mastoidectomy with meatoplasty is the surgical technique recommended for repairing the mastoid and the facial nerve. In the majority of cases, a cable graft is necessary. Since nerve lesion in proximity to the stylomastoid foramen and extratemporal facial nerve is common, these areas must be explored carefully.  相似文献   
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Colorectal cancer (CRC) is found among those with greatest frequency and exponential increase worldwide, with high mortality rates, which are observed as increasing due to the postsurgical complications that come to present. Systemic inflammation participates in the development and progression of cancer; therefore, inflammatory and/or immunological response markers such as the neutrophil/lymphocyte index (NLI) can aid us in predicting the poor results of our interventions. The purpose of our study was to determine the impact of an NLI of ≥2.6 as a predictor of early postsurgical complications. By means of a prospective cohort, we analyzed 158 patients with CRC who were submitted to elective surgery with a later 30-day follow-up. We found that the preoperatory NLI of ≥2.6 obtained an odds ratio (OR) = 2.24 (95% confidence interval [CI], 1.15-4.36) as a prognostic factor of early postsurgical complications according to the Clavien-Dindo classification scale, which represents a low prognostic impact due to its predictive yield with low accuracy, which is the opposite of what other reports have previously published. The use of chemotherapy before the surgical procedure was also determined to be a risk factor for post-surgical complications.  相似文献   
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Titanium oxide (TiO2) has been widely investigated as a photocatalytic material, and the fact that its performance depends on its crystalline structure motivates further research on the relationship between preparation methods and material properties. In this work, TiO2 thin films were grown on non-functionalized wave-like patterned vertically aligned carbon nanotubes (w-VA-CNTs) via the atomic layer deposition (ALD) technique. Grazing incidence X-ray diffraction (GIXRD) analysis revealed that the structure of the TiO2/VA-CNT nanocomposites varied from amorphous to a crystalline phase with increasing deposition temperature, suggesting a “critical deposition temperature” for the anatase crystalline phase formation. On the other hand, scanning transmission electron microscopy (STEM) studies revealed that the non-functionalized carbon nanotubes were conformally and homogeneously coated with TiO2, forming a nanocomposite while preserving the morphology of the nanotubes. X-ray photoelectron spectroscopy (XPS) provided information about the surface chemistry and stoichiometry of TiO2. The photodegradation experiments under ultraviolet (UV) light on a model pollutant (Rhodamine B, RhB) revealed that the nanocomposite comprised of anatase crystalline TiO2 grown at 200 °C (11.2 nm thickness) presented the highest degradation efficiency viz 55% with an illumination time of 240 min. Furthermore, its recyclability was also demonstrated for multiple cycles, showing good recovery and potential for practical applications.

Amorphous or anatase crystalline TiO2/VA-CNT nanocomposites were grown controlling the synthesis temperature. Photocatalytic degradation of RhB of 55% was achieved after 240 min. The immobilized material remains active after 4 cycles of use.  相似文献   
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