643 research outputs found
Polynomial Total Positivity and High Relative Accuracy Through Schur Polynomials
In this paper, Schur polynomials are used to provide a bidiagonal decomposition of polynomial collocation matrices. The symmetry of Schur polynomials is exploited to analyze the total positivity on some unbounded intervals of a relevant class of polynomial bases. The proposed factorization is used to achieve relative errors of the order of the unit round-off when solving algebraic problems involving the collocation matrix of relevant polynomial bases, such as the Hermite basis. The numerical experimentation illustrates the accurate results obtained when using the findings of the paper
Temperature and particle concentration influence on the complex viscous behavior of a hydrophilic fumed silica suspension
Shear-thinning behavior (decrease of the apparent steady viscosity with shear) due to breaking of weak particle flocs and posterior alignment of individual particles in layers parallel to the flow direction is usually observed before the appearance of the shear-thickening behavior (increase of the apparent steady viscosity with shear). The shear-thickening behavior is mainly due to the dominant role played by hydrodynamic over Brownian and colloidal forces at relatively high shear. As a rule, the onset of shear-thickening behavior and the maximum viscosity value appear at lower shear rates when solid concentration increases, and temperature decreases. However, the influence of solid concentration and temperature on shear stress characteristic values have received less attention despite being the shear stress the true cause of microstructure changes that can provoke the appearance of the shear-thickening behaviour. A recently published empirical equation for the shear stress dependence of the steady viscosity of shear thickening fluids [T. Shende, V.J. Niasar, M. Babaei, J. Mol. Liq. 325 (2021) 115220] has been used for fitting experimental data (MARSIII, Thermo-Haake, Germany) of a hydrophilic fumed silica suspension (A200 (Evonik, Germany) in PPG400 (Sigma-Aldrich, Germany)). The influence of temperature (10,\ 30,\ 50,\ 70\degc) and solid concentration (10,\ 15,\ 20,\ 25%\ wt) on the shear-thickening behavior has been monitored recording their influence on the model parameters.Universidad de Málaga. Campus de Excelencia Internacional AndalucÃa Tech
Territorios-laboratorio
La crisis de la planificación territorial, cuyo diagnóstico se realiza sintéticamente, reside, aunque sólo parcialmente, en su carencia de estatuto cientÃfico. Las disciplinas del territorio deben renovarse a fondo: nada ha ocurrido nunca al margen de la materialidad del territorio. La comunicación presenta un desarrollo parcial del concepto de territorio-laboratorio que se ha elaborado, como operación de desgajar un fragmento del resto del territorio, teniendo en cuenta experiencias investigadoras concretas. Se pretende el análisis del cambio territorial (y urbano) a partir de la delimitación precisa de ciertos fragmentos territoriales, a distintas escalas (micro, intermedias y macro), que sirvan de laboratorio (estable en el tiempo), para definir instrumentos (evaluación de variables, matrices territoriales y de territorialidad, sotfware especÃfico y cartografÃa) que acerquen con mayor precisión a la comprensión del cambio territorial y sus patrones. Se concretan tales laboratorios en las escalas mencionadas para el caso de AndalucÃa
Metastatic colorectal cancer: integrating irinotecan into combination and sequential chemotherapy
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Treatment patterns for metastatic colorectal cancer in Spain
Abstract Purpose The primary aim of this retrospective study was to describe the treatment patterns according to the type of treatment received by patients with metastatic colorectal cancer (mCRC) in Spain. Methods This was a retrospective, observational, multicenter study performed by 33 sites throughout Spain that included consecutive patients aged 18 years or older who had received or were receiving treatment for mCRC. Results At the time of inclusion, of the 873 evaluable patients, 507 (58%) had received two lines, 235 (27%) had received three lines, 106 (12%) had received four lines, and the remaining patients had received up to ten lines. The most frequent chemotherapy schemes were the FOLFOX or CAPOX regimens (66%) for frst-line treatment, FOLFOX, CAPOX or FOLFIRI (70%) for second-line treatment, and FOLFOX, FOLFIRI or other fuoropyrimidine-based regimens for third- and fourth-line (over 60%) treatment. Sixty percent of patients received targeted therapy as part of their frst-line treatment, and this proportion increased up to approximately 70% of patients as part of the second-line of treatment. A relevant proportion of patients were treated with unknown KRAS, and especially the BRAF, mutation statuses. Conclusions This study reveals inconsistencies regarding adherence to the recommendations of the ESMO guidelines for the management of mCRC in Spain. Improved adherence to the standard practice described in such guidelines for the determination of RAS and BRAF mutation statuses and the use of targeted therapies in frst-line treatment should be considered to guarantee that patients can beneft from the best therapeutic approaches available. Keywords Colorectal cancer · Metastatic · Treatment patterns · KRAS/BRAF mutation status · Clinical practice guidelin
Phase I/II study of oxaliplatin with oral S-1 as first-line therapy for patients with metastatic colorectal cancer
Two phase II studies of S-1 monotherapy have shown promising response rates (RR) of 35–40% with good tolerability in patients with untreated metastatic colorectal cancer. To investigate the usefulness of S-1 plus oxaliplatin (SOX) as an alternative to infusional 5-fluorouracil/leucovorin plus oxaliplatin, the recommended dose (RD) of SOX was determined, and its safety and preliminary efficacy were evaluated in a phase I/II study. Oxaliplatin was administered at a dose of 100 mg m−2 (level 1) or 130 mg m−2 (level 2) on day 1, and S-1 (80–120) was given twice daily for 2 weeks followed by a 1-week rest. This schedule was repeated every 3 weeks. Level 2 was determined to be the RD. For the 28 patients who received the RD, the median treatment course was 6.5 cycles (2–14), RR of 50% (1 CR and 13 PR: 95% CI 31–69%), with a median progression-free survival of 196 days. Survival rate (1 year) was 79%. Peripheral neuropathy was observed in all patients but with no functional disorders. Major grade 3 or 4 adverse reactions at the RD were neutropaenia (14%), thrombocytopaenia (28%), and diarrhoea (3%). SOX regimen is effective and easily manageable without central vein access
XELOX vs FOLFOX-4 as first-line therapy for metastatic colorectal cancer: NO16966 updated results
BACKGROUND: We report updated overall survival (OS) data from study NO16966, which compared capecitabine plus oxaliplatin (XELOX) vs 5-fluorouracil/folinic acid plus oxaliplatin (FOLFOX4) as first-line therapy in metastatic colorectal cancer.
METHODS: NO16966 was a randomised, two-arm, non-inferiority, phase III comparison of XELOX vs FOLFOX4, which was subsequently amended to a 2 x 2 factorial design with further randomisation to bevacizumab or placebo. A planned follow-up exploratory analysis of OS was performed.
RESULTS: The intent-to-treat (ITT) population comprised 2034 patients (two-arm portion, n = 634; 2 x 2 factorial portion, n 1400). For the whole NO16966 study population, median OS was 19.8 months in the pooled XELOX/XELOX-placebo/XELOX-bevacizumab arms vs 19.5 months in the pooled FOLFOX4/FOLFOX4-placebo/FOLFOX4-bevacizumab arms (hazard ratio 0.95 (97.5% CI 0.85-1.06)). In the pooled XELOX/XELOX-placebo arms, median OS was 19.0 vs 18.9 months in the pooled FOLFOX4/FOLFOX4-placebo arms (hazard ratio 0.95 (97.5% CI 0.83-1.09)). FOLFOX4 was associated with more grade 3/4 neutropenia/granulocytopenia and febrile neutropenia than XELOX, and XELOX with more grade 3 diarrhoea and grade 3 hand-foot syndrome than FOLFOX4.
CONCLUSION: Updated survival data from study NO16966 show that XELOX is similar to FOLFOX4, confirming the primary analysis of progression-free survival. XELOX can be considered as a routine first-line treatment option for patients with metastatic colorectal cancer
Working towards a consensus on the oncological approach of breakthrough pain: A Delphi survey of Spanish experts
Purpose: There is a lack of standards for the diagnosis, assessment and management of breakthrough cancer pain (BTcP). La Fundación ECO (the Foundation for Excellence and Quality in Oncology) commissioned a study to establish a consensus and lay the foundations for the appropriate management of BTcP in oncology patients.
Patients and methods: A modified Delphi survey comprising two rounds was used to gather and analyze data, which was conducted over the Internet. Each statement that reached a consensus with the respondents was defined as a median consensus score (MED) of =7, and agreement among panelists as an interquartile range (IQR) of =3.
Results: In total, 69 medical oncologists responded, with a broad consensus that BTcP implied exacerbations of high-intensity pain, as opposed to moderate pain. Furthermore, they concurred that appropriate diagnostic equipment is needed, and that rapid-onset fentanyl formulations should be the preferred treatment for BTcP management. The panelists agreed that a lack of appropriate information and training to attend to patients, as well as limited patient visitation rights, were barriers to effective BTcP management. Regarding gaps in detected knowledge, the panelists were unsure of the measures necessary to assess the burden of the disease on the patient’s quality of life and associated medication costs. Alongside this, there was a lack of awareness of the technical specifics of the different formulations of rapid-onset fentanyl.
Conclusion: These results represent the current status of BTcP management. They may inform recommendations and provide a framework for future research
Incorporating BEAMing technology as a liquid biopsy into clinical practice for the management of colorectal cancer patients : an expert taskforce review
The importance of mutation identification for advanced colorectal cancer treatment with anti-epidermal growth factor receptor agents is well established. However, due to delays in turnaround time, low-quality tissue samples, and/or lack of standardization of testing methods a significant proportion of patients are being treated without the information that Kirsten rat sarcoma and neuroblastoma rat sarcoma (RAS) testing can provide. The detection of mutated circulating tumor DNA by BEAMing technology addresses this gap in care and allows these patients to receive international guideline-recommended expanded RAS testing with rapid turnaround times. Furthermore, the overall concordance between OncoBEAM RAS colorectal cancer testing and standard of care tissue testing is very high (93.3%). This article presents an overview of the clinical utility and potential applications of this minimally invasive method, such as early detection of emergent resistance to anti-epidermal growth factor receptor therapy. If appropriately implemented, BEAMing technology holds considerable promise to enhance the quality of patient care and improve clinical outcomes
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