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Predicting Survival (predicting + survival)
Selected AbstractsPredicting survival of grass shrimp (Palaemonetes pugio) exposed to naphthalene, fluorene, and dibenzothiophene,ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 8 2008Michael A. Unger Abstract The composition and persistence of dissolved polycyclic aromatic hydrocarbons (PAHs) released to the water column during oil spills are altered by weathering, tidal transport, and addition of dispersants. Conventional toxicity effect metrics, such as the median lethal concentration (LC50), are inaccurate predictors of mortality from all toxicant exposure duration/concentration combinations likely to occur during spills. In contrast, survival models can predict the proportions of animals dying as a consequence of exposures differing in duration and intensity. Extending previous work with ethylnaphthalene, dimethylnaphthalene, and phen-anthrene, survival time models were developed that include exposure duration and concentration to predict time to death for grass shrimp (Palaemonetes pugio). Two additional PAHs (naphthalene and fluorene) and a heterocyclic aromatic hydrocarbon (dibenzothiophene) were evaluated for the present study. Preliminary explorations of these models confirmed that quantitative structure-activity regression models were possible for predicting survival model parameters from compound characteristics. Conventional 48-h LC50s also were calculated for the compounds and combined with published LC50s to predict relative PAH toxicity to P. pugio based on octanol-water partitioning. [source] Predicting survival in adults with invasive aspergillosis during therapy for hematological malignancies or after hematopoietic stem cell transplantation: Single-center analysis and validation of the Seattle, French, and Strasbourg prognostic indexes,AMERICAN JOURNAL OF HEMATOLOGY, Issue 9 2009Rocio Parody In this retrospective monocenter study, we analyzed the outcomes of 130 adult hematological patients who developed a proven (n = 23), probable (n = 71), and possible (n = 36) invasive aspergillosis (IA) in a 13-year period. Forty-nine patients (38%) were recipients of an allogeneic hematopoietic stem cell transplantation (AlloHSCT). The main goal of the study was the identification of prognostic factors for 4-month aspergillosis free survival (AFS) and overall survival (OS). IA was identified as the main cause of death in 27/49 recipients of an AlloHSCT (55%) and 28/81 nontransplanted patients (35%). Diagnosis of IA at or before 2000 had a negative impact in both 4-month AFS and 4-month OS in the entire group. In multivariate analysis performed separately for nontransplanted and allo-HSCT patients, five variables (excluding the year of diagnosis) decreased 4-month AFS: (i) impairment of one organ function (OF), (ii) impairment of two or more OFs (two points), (iii) disseminated IA, (iv) neutropenia lasting more than 10 days (non-AlloHSCT group only) or monocytopenia (<0.1 × 109/l) [AlloHSCT group only], and (v) high-dose steroids (non-AlloHSCT group only) or an alternative donor (AlloHSCT group only). According to the number of adverse risk factors, three prognostic subgroups were defined in non-transplanted and alloHSCT patients with good (97% and 78% AFS), intermediate (73% and 32% AFS) and poor prognosis (20% and 11% AFS) of IA [P < 0.01]. In addition, we validated the French and Seattle prognostic indexes for allo-HSCT recipients and the Strasbourg model for all hematological patients with IA. Am. J. Hematol., 2009. © 2009 Wiley-Liss, Inc. [source] Ecological relevance of laboratory determined temperature limits: colonization potential, biogeography and resilience of Antarctic invertebrates to environmental changeGLOBAL CHANGE BIOLOGY, Issue 11 2010D. K. A. BARNES Abstract The relevance of laboratory experiments in predicting effects of climate change has been questioned, especially in Antarctica where sea temperatures are remarkably stable. Laboratory studies of Southern Ocean marine animal capacities to survive increasing temperature mainly utilize rapid temperature elevations, 100 ×,10 000 × faster than sea temperature is predicted to rise. However, due to small-scale temperature fluctuations these studies may be crucial for understanding colonization patterns and predicting survival particularly through interactions between thermal tolerance and migration. The colonization of disjunct shelves around Antarctica by larvae or adult drift requires crossing or exposure to, rapid temperature changes of up to 2,4 °C over days to weeks. Analyses of responses to warming at varying rates of temperature change in the laboratory allow better predictions of the potential species have for colonizing disjunct shelf areas (such as the Scotia Arc). Inhabiting greater diversities of localities increases the geographic and thermal range species experience. We suggest a strong link between short-term temperature tolerance, environmental range and prospects for surviving changing environments. [source] Absolute lymphocyte count at the time of first relapse predicts survival in patients with diffuse large B-cell lymphomaAMERICAN JOURNAL OF HEMATOLOGY, Issue 2 2009Luis F. Porrata Peripheral blood absolute lymphocyte count (ALC) is a survival prognostic factor in hematological malignancies. No reports have addressed whether ALC at the time of first relapse (ALC-R) predicts survival. Thus, we assessed the prognostic significance of ALC-R in diffuse large B-cell lymphoma (DLBCL). Patients were required to have been diagnosed with first relapsed DLBCL, have ALC-R values, and to be followed at Mayo Clinic, Rochester. From Feb 1987 until March 2006, 97 first relapsed DLBCL patients qualified for the study. The overall survival (OS) and progression-free survival (PFS) were measured from the time of first relapse. The value of ALC- R , 1.0 × 109/L was used for the analysis. Both groups (ALC-R , 1 or < 1 × 109/L) were balanced for the international prognostic index at relapse (IPI-R) (P = 0.3), and for autologous stem cell transplantation (P = 0.4). Superior OS and PFS were observed with an ALC-R , 1.0 × 109/L (N = 60) versus ALC-R < 1.0 × 109/L (N = 37) [median OS: 28.7 months, 5 years OS rates of 39% versus median OS: 10.2 months, 5 years OS rates of 14%, P < 0.002; and median PFS: 14.8 months, 5 years PFS rates of 21% versus median PFS: 6.5 months, 5 years PFS rates of 8%, P < 0.004, respectively]. ALC-R was an independent prognostic factor for OS [RR = 0.4, P < 0.01] and PFS [RR = 0.5, P < 0.005]. ALC-R predicts survival suggesting that host immunity is an important variable predicting survival in first relapsed DLBCL. Am. J. Hematol. 2009. © 2008 Wiley-Liss, Inc. [source] Validation and simplification of a score predicting survival in patients irradiated for metastatic spinal cord compressionCANCER, Issue 15 2010Dirk Rades MD Abstract BACKGROUND: Based on an analysis of 1852 retrospectively evaluated patients with metastatic spinal cord compression (MSCC), a scoring system was developed to predict survival. This study was performed to validate the scoring system in a new data set. METHODS: The score included 6 prognostic factors: tumor type, interval between tumor diagnosis and MSCC, other bone or visceral metastases, ambulatory status, and duration of motor deficits. Scores ranged between 20 and 45 points, and patients were initially divided into 5 groups: those with 20 to 25 points, those with 26 to 30 points, those with 31 to 35 points, those with 36 to 40 points, and those with 41 to 45 points. To facilitate the clinical use of the score, the patients were regrouped into 3 groups: those with 20 to 30 points, those with 31 to 35 points, and those with 36 to 45 points. In this study, data of 439 new patients were included who were divided into the same prognostic groups as in the preceding study. RESULTS: In this study, the 6-month survival rates were 7% (for those with 20-25 points), 19% (for those with 26-30 points), 56% (for those with 31-35 points), 73% (for those with 36-40 points), and 90% (for those with 41-45 points), respectively (P < .0001). After regrouping, the 6-month survival rates were 14% (for those with 20-30 points), 56% (for those with 31-35 points), and 80% (for those with 36-45 points), respectively, in this study (P < .0001). CONCLUSIONS: In the current study, the difference in 6-month survival between the prognostic groups was found to be as significant as in the preceding study. Thus, this scoring system was considered valid to estimate survival of MSCC patients. The system could have been simplified by including only 3 instead of 5 prognostic groups. Cancer 2010. © 2010 American Cancer Society. [source] Construction of the Chinese University Prognostic Index for hepatocellular carcinoma and comparison with the TNM staging system, the Okuda staging system, and the Cancer of the Liver Italian Program staging systemCANCER, Issue 6 2002A study based on 926 patients Abstract BACKGROUND The current TNM staging system for patients with hepatocellular carcinoma (HCC) does not include liver function parameters and does not provide a precise prognosis for patients in different risk groups. The objectives of this study were to construct a new prognostic index for patients with hepatocellular carcinoma, the Chinese University Prognostic Index (CUPI), and to compare it with existing staging systems in terms of their ability to classify patients into different risk group. METHODS From 1996 to 1998, 926 ethnic Chinese patients who were diagnosed with HCC (mainly hepatitis B-associated) at a single institution were recruited prospectively into this study. A multivariate analysis on 19 patient characteristics was performed using a Cox regression model to identify independent prognostic factors. Weights were derived from the regression coefficients of various factors to construct the CUPI. Patients were classified according to different staging systems. Survival curves were plotted with the Kaplan,Meier method and were compared by using a log-rank test. RESULTS Both the TNM staging system and the Okuda staging system had prognostic significance, but the significance was lower for the Cancer of the Liver Italian Program (CLIP) prognostic score among the patients in the study population. The CUPI was constructed by adding the following factors into the TNM staging system: total bilirubin, ascites, alkaline phosphatase, , fetoprotein, and asymptomatic disease on presentation. The new CUPI characterized three risk groups with highly significant differences in survival during the whole period of follow-up (P < 0.00001) and was more discriminant than the other systems. CONCLUSIONS In the study population of patients with mainly hepatitis B-associated HCC, the CUPI was more discriminant than the TNM staging system, the Okuda staging systems, or the CLIP prognostic score in classifying patients into different risk groups and was better at predicting survival. The CUPI needs to be validated by different cohorts of patients before it can be recommended for general use. Cancer 2002;94:1760,9. © 2002 American Cancer Society. DOI 10.1002/cncr.10384 [source] | |||||||||||||