97 research outputs found
Oxidative stress in hepatitis C infected end-stage renal disease subjects
BACKGROUND: Both uremia and hepatitis C infection is associated with increased oxidative stress. In the present study, we aimed to find out whether hepatitis C infection has any impact on oxidative stress in hemodialysis subjects. METHODS: Sixteen hepatitis C (+) hemodialysis subjects, 24 hepatitis C negative hemodialysis subjects and 24 healthy subjects were included. Total antioxidant capacity, total peroxide level and oxidative stress index were determined in all subjects. RESULTS: Total antioxidant capacity was significantly higher in controls than hemodialysis subjects with or without hepatitis C infection (all p < 0.05/3), while total peroxide level and oxidative stress index were significantly lower (all p < 0.05/3). Hepatitis C (-) hemodialysis subjects had higher total antioxidant capacity compared to hepatitis C (+) hemodialysis subjects (all p < 0.05/3). Total peroxide level and oxidative stress index was comparable between hemodialysis subjects with or without hepatitis C infection (p > 0.05/3). CONCLUSION: Oxidative stress is increased in both hepatitis C (+) and hepatitis C (-) hemodialysis subjects. However, hepatitis C infection seems to not cause any additional increase in oxidative stress in hemodialysis subjects and it may be partly due to protective effect of dialysis treatment on hepatitis C infection
A ROC analysis-based classification method for landslide susceptibility maps
[EN] A landslide susceptibility map is a crucial tool for landuse spatial planning and management in mountainous areas. An essential issue in such maps is the determination of susceptibility thresholds. To this end, the map is zoned into a limited number of classes. Adopting one classification system or another will not only affect the map's readability and final appearance, but most importantly, it may affect the decision-making tasks required for effective land management. The present study compares and evaluates the reliability of some of the most commonly used classification methods, applied to a susceptibility map produced for the area of La Marina (Alicante, Spain). A new classification method based on ROC analysis is proposed, which extracts all the useful information from the initial dataset (terrain characteristics and landslide inventory) and includes, for the first time, the concept of misclassification costs. This process yields a more objective differentiation of susceptibility levels that relies less on the intrinsic structure of the terrain characteristics. The results reveal a considerable difference between the classification methods used to define the most susceptible zones (in over 20% of the surface) and highlight the need to establish a standard method for producing classified susceptibility maps. The method proposed in the study is particularly notable for its consistency, stability and homogeneity, and may mark the starting point for consensus on a generalisable classification method.Cantarino-Martí, I.; Carrión Carmona, MÁ.; Goerlich-Gisbert, F.; Martínez Ibáñez, V. (2018). A ROC analysis-based classification method for landslide susceptibility maps. Landslides. 1-18. doi:10.1007/s10346-018-1063-4S118Armstrong MP, Xiao N, Bennett DA (2003) Using genetic algorithms to create multicriteria class intervals for choropleth maps. 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Biopsy of the scalene fat pad in carcinoma of the cervix uteri metastatic to the periaortic lymph nodes.
Fifty-five patients with squamous cell carcinoma of the cervix uteri metastatic to high common iliac or periaortic lymph nodes underwent biopsy of the left scalene fat pad as part of a prospective clinical trial. Patients without metastasis to the scalene nodes were subsequently treated with extended field radiation therapy and were then eligible for a randomized trial of systemic chemotherapy. Only four patients were found to have micrometastases to the scalene fossa. This figure is appreciably lower than that reported in previous literature. While geographic failure continues to be a problem for this group of patients, routine use of left scalene fat pad biopsy before treatment is not recommended
Cisplatin, radiation, and adjuvant hysterectomy compared with radiation and adjuvant hysterectomy for bulky stage IB cervical carcinoma.
BACKGROUND: Bulky stage IB cervical cancers have a poorer prognosis than smaller stage I cervical cancers. For the Gynecologic Oncology Group, we conducted a trial to determine whether weekly infusions of cisplatin during radiotherapy improve progression-free and overall survival among patients with bulky stage IB cervical cancer.
METHODS: Women with bulky stage IB cervical cancers (tumor, \u3e or =4 cm in diameter) were randomly assigned to receive radiotherapy alone or in combination with cisplatin (40 mg per square meter of body-surface area once a week for up to six doses; maximal weekly dose, 70 mg), followed in all patients by adjuvant hysterectomy. Women with evidence of lymphadenopathy on computed tomographic scanning or lymphangiography were ineligible unless histologic analysis showed that there was no lymph-node involvement. The cumulative dose of external pelvic and intracavitary radiation was 75 Gy to point A (cervical parametrium) and 55 Gy to point B (pelvic wall). Cisplatin was given during external radiotherapy, and adjuvant hysterectomy was performed three to six weeks later.
RESULTS: The relative risks of progression of disease and death among the 183 women assigned to receive radiotherapy and chemotherapy with cisplatin, as compared with the 186 women assigned to receive radiotherapy alone, were 0.51 (95 percent confidence interval, 0.34 to 0.75) and 0.54 (95 percent confidence interval, 0.34 to 0.86), respectively. The rates of both progression-free survival (P
CONCLUSIONS: Adding weekly infusions of cisplatin to pelvic radiotherapy followed by hysterectomy significantly reduced the risk of disease recurrence and death in women with bulky stage IB cervical cancers
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