Search results for "surrogate"
showing 10 items of 145 documents
Cross-taxon congruence and relationships to stand characteristics of vascular plants, bryophytes, polyporous fungi and beetles in mature managed bore…
2018
Abstract Multi-taxon analyses of ecological assemblages are needed when the effects of forestry on biodiversity are examined. Management usually simplifies the structure of forests, which results in quantitative and qualitative declines in many microhabitats and species associated with them. In Fennoscandia, most forests are managed for industrial use of wood, but relatively little is known about the relationships between structural components and biodiversity in managed forests. Abundance, composition or species number of different species groups reacting similarly to variation in their environment would be a useful tool e.g. in estimating responses of species that are more difficult to sa…
One taxon does not fit all: Herb-layer diversity and stand structural complexity are weak predictors of biodiversity in Fagus sylvatica forests
2016
Abstract Since adequate information on the distribution of biodiversity is hardly achievable, biodiversity indicators are necessary to support the management of ecosystems. These surrogates assume that either some habitat features, or the biodiversity patterns observed in a well-known taxon, can be used as a proxy of the diversity of one or more target taxa. Nevertheless, at least for certain taxa, the validity of this assumption has not yet been sufficiently demonstrated. We investigated the effectiveness of both a habitat- and a taxa-based surrogate in six European beech forests in the Apennines. Particularly, we tested: (1) whether the stand structural complexity and the herb-layer speci…
A survey on handling computationally expensive multiobjective optimization problems with evolutionary algorithms
2017
Evolutionary algorithms are widely used for solving multiobjective optimization problems but are often criticized because of a large number of function evaluations needed. Approximations, especially function approximations, also referred to as surrogates or metamodels are commonly used in the literature to reduce the computation time. This paper presents a survey of 45 different recent algorithms proposed in the literature between 2008 and 2016 to handle computationally expensive multiobjective optimization problems. Several algorithms are discussed based on what kind of an approximation such as problem, function or fitness approximation they use. Most emphasis is given to function approxim…
Duration of previous treatment as a prognostic factor in metastatic colorectal cancer treated with trifluridine/tipiracil
2018
We herein describe the findings from the trifluridine/tipiracil (TAS-102) Compassionate Use program in Latvia, set up prior to marketing authorization for the management of pretreated patients with metastatic colorectal cancer (mCRC). The efficacy and safety of TAS-102 in patients with refractory mCRC were evaluated in the phase III trial RECOURSE. A previous report confirmed neutropenia and duration of previous treatment for mCRC as prognostic factors in TAS-102 users. The aim of the present study was to analyze possible prognostic factors, such as neutropenia, in TAS-102 responders. A retrospective analysis of 14 patients who received TAS-102 chemotherapy in two institutions in Latvia (Cl…
First international descriptive and interventional survey for cholesterol and non-cholesterol sterol determination by gas- and liquid-chromatography–…
2019
International audience; Serum concentrations of lathosterol, the plant sterols campesterol and sitosterol and the cholesterol metabolite 5alpha-cholestanol are widely used as surrogate markers of cholesterol synthesis and absorption, respectively. Increasing numbers of laboratories utilize a broad spectrum of well-established and recently developed methods for the determination of cholesterol and non-cholesterol sterols (NCS). In order to evaluate the quality of these measurements and to identify possible sources of analytical errors our group initiated the first international survey for cholesterol and NCS. The cholesterol and NCS survey was structured as a two-part survey which took place…
Longitudinal study of DNA methylation during the first 5 years of life
2016
[Background]: Early life epigenetic programming influences adult health outcomes. Moreover, DNA methylation levels have been found to change more rapidly during the first years of life. Our aim was the identification and characterization of the CpG sites that are modified with time during the first years of life. We hypothesize that these DNA methylation changes would lead to the detection of genes that might be epigenetically modulated by environmental factors during early childhood and which, if disturbed, might contribute to susceptibility to diseases later in life. [Methods]: The study of the DNA methylation pattern of 485577 CpG sites was performed on 30 blood samples from 15 subjects,…
Effects of Immunonutrition in Advanced Human Immunodeficiency Virus Disease: A Randomized Placebo-controlled Clinical Trial (Promaltia Study)
2018
[Background]: While nutritional interventions with prebiotics and probiotics seem to exert immunological effects, their clinical implications in human immunodeficiency virus (HIV)–infected subjects initiating antiretroviral therapy (ART) at advanced HIV disease remain unclear.
Baseline Splenic Volume as a Prognostic Biomarker of FOLFIRI Efficacy and a Surrogate Marker of MDSC Accumulation in Metastatic Colorectal Carcinoma
2020
Background: Predictive biomarkers of response to chemotherapy plus antiangiogenic for metastatic colorectal cancer (mCRC) are lacking. The objective of this study was to test the prognostic role of splenomegaly on baseline CT scan. Methods: This study is a sub-study of PRODIGE-9 study, which included 488 mCRC patients treated by 5-fluorouracil, leucovorin and irinotecan (FOLFIRI) and bevacizumab in first line. The association between splenic volume, and PFS and OS was evaluated by univariate and multivariable Cox analyses. The relation between circulating monocytic Myeloid derived suppressor cells (mMDSC) and splenomegaly was also determined. Results: Baseline splenic volume >
The Role of Molecular Profiling to Predict the Response to Immune Checkpoint Inhibitors in Lung Cancer.
2019
Immune checkpoint inhibitors radically changed the treatment of patients with non-small cell lung cancer (NSCLC). However, only one-quarter of patients benefit from these new therapies when used as monotherapy. The assessment of Program Death Ligand-1 (PD-L1) tumor expression by immunohistochemistry is used to select potential responder patients, but this not an optimal marker since it does not predict the absence of anti PD-1 efficacy. Despite this shortcoming, PD-L1 remains the gold standard biomarker in many studies and the only biomarker available for clinicians. In addition to histological markers, transcriptomic and exome analyses have revealed potential biomarkers requiring further c…
Progression-free survival as a surrogate endpoint of overall survival in patients with metastatic colorectal cancer
2018
Giuseppe Cicero,1 Rossella De Luca,1 Francesco Dieli2 1Department of Surgical, Oncological and Oral Sciences, Section of Medical Oncology, University of Palermo, Palermo, Italy; 2Central Laboratory of Advanced Diagnosis and Biomedical Research (CLADIBIOR), University of Palermo, Palermo, Italy Background: In many clinical trials designed to assess the efficacy of anticancer treatments, overall survival (OS) is often used as a primary endpoint despite its several points of weakness. Methods: This study evaluated the role of progression-free survival (PFS) in the first three lines of treatment as a potential surrogate endpoint of OS in patients with metastatic colorectal cancer (MCRC). One hu…