183 research outputs found
Astenia en cáncer avanzado y uso de psicoestimulantes
Asthenia is the most frequent symptom in patients
with advanced cancer and is probably what most
affects the quality of life of oncology patients since it interferes
in their physical and social activity. Treatment
in the majority of cases is symptomatic. There is
growing interest in the use of psychostimulants for treating
asthenia. Methylphenidate and modafinil are two
psychostimulants that have already been tested in controlled
studies on asthenia of the patient with advanced
cancer; they have proved to be efficient, particularly in
patients in very advanced stages who are very tired
Structural and catalytic properties of lanthanide (La, Eu, Gd) doped ceria
Este documento es la última versión enviada a la revista con los ajustes finales después de la revisión de los evaluadores.In this work, Ce0.9M0.1O2−δ mixed oxides (M=La, Eu and Gd) were synthesized by coprecipitation. Independent of the dopant cation, the obtained solids maintain the F-type crystalline structure, characteristic of CeO2 (fluorite structure) without phase segregation. The ceria lattice expands depending on the ionic radii of the dopant cation, as indicated by X-ray diffraction studies. This effect also agrees with the observed shift of the F2g Raman vibrational mode. The presence of the dopant cations in the ceria lattice increases the concentration of structural oxygen vacancies and the reducibility of the redox pair Ce4+/Ce3+. All synthesized materials show higher catalytic activity for the CO oxidation reaction than that of bare CeO2, being Eu-doped solid the one with the best catalytic performances despite of its lower surface area.Junta de Andalucía con su apoyo a la unidad TEP106Ministerio de Ciencia e Innovación mediante la subvención del proyecto: ENE2009-14522-C05-01 cofinanciado con fondos FEDER de la Unión EuropeaPrograma Alban a través de la beca predoctoral de W.Y. Hernández: (E06D101739CO
Catalytic oxidation of emissions in combustion systems for forest biomass, using catalysts with TiO2 support
A study was made of the catalytic oxidation of a model mixture of effluents from forest biomass combustion equipment, consisting principally of methane (CH4), naphthalene (C10H8), carbon monoxide (CO) and oxygen-poor air (10% O2, balance N2), in a laboratory reactor, using MeOx/TiO2 catalysts (Me = Fe, Cu or Mn), prepared using incipient wetness impregnation. It was observed that the addition of metal oxides to the TiO2 increases catalytic activity in the combustion of all the contaminants present in the model effluent (CH 4, C10H8 and CO). The catalysts were characterised using the following techniques: SBET, XRD, DTG/DTA and TPD-NH 3; and from these it was observed that the support presented only the anatase phase in all the catalysts, despite having been subjected to temperatures in excess of 1.000 K during combustion. The highest acidity among all the solids tested, measured by TPD-NH3, was obtained for the FeOx/TiO2 catalysts, which were also those which showed the greatest catalytic activity. This high level of activity may be related to the formation of isolated metallic phases; i.e. hematite (Fe2O3), which would be the active phase in the combustion of C10H8 and CH4. On the other hand, with to respect to the 5 % wt. values of Me/TiO2 (Me: Fe, Cu y Mn) catalysts, the CuO/TiO2 catalyst shows greater activity than Fe2O3/TiO2 and MnOx/TiO2 for the oxidation of CO, which would be related to the formation of CuO on the TiO2 surface. The formation of mixed phases between the metals and the TiO2 was not observed. The SBET of the most active catalyst, Fe2O3/TiO2 (where Fe is 5% w/w in value), was not subject to any changes during the reaction
CO oxidation: effect of Ce and Au addition on MnOx catalysts
The effect of cerium and/or gold addition to a manganese oxide which was greatly active in CO oxidation was studied. The catalysts obtained by this way were characterized by N2 adsorption, XRF, XRD and TPR, and their catalytic activity was measured in the CO oxidation reaction. The pure MnOx catalyst was active in the CO oxidation but the addition of 5 wt % cerium decreased their catalytic activity. Adding 2 wt % gold improved the activity of MnOx and Ce/MnOx and caused a slight decrease of the catalyst specific area and of the average oxidation state of manganese in catalysts, which was found between 3.3 and 3.6. The order of activity found on the basis of T50 for the four catalysts was: Au/MnOx > Au/Ce/MnOx > MnOx > Ce/MnOx, with T50 of 89, 95, 99 and 139 ºC, respectively. The solids Au/MnOx and Au/Ce/MnOx presented a T10 of 30 and 49 ºC, indicating that gold favored the conversion at room temperature. The effect of water vapor on the reaction was also analyzed, finding a decrease in the catalytic activity of all catalysts, due to the blocking of active sites in the catalyst surfaceUnión Europea AlBan UE E06D101739C
Performance of AISI 316L-stainless steel foams towards the formation of graphene related nanomaterials by catalytic decomposition of methane at high temperature
This work explores the preparation of graphene-related materials (GRMs) grown on stainless steel foams via catalytic decomposition of methane (CDM). The main active phases for the reaction are the Fe nanoparticles segregated from the stainless-steel after the activation stage of the foam. The effect of the feed composition and reaction temperature has been studied in order to maximize the productivity, stability and selectivity to GRMs. The maximum productivity attained was 0.116 gC/gfoam h operating at 950 °C with a feed ratio of CH4/H2 = 3 (42.9 %CH4:14.3 %H2). The carbonaceous nanomaterials (CNMs) obtained were characterized by X-Ray diffraction, Raman spectroscopy and by transmission and scanning electron microscopy. The parameters of the kinetic model developed are directly related to the relevant stages of the process, including carburization, diffusion-precipitation and deactivation-regeneration. The balance among these sequential stages determines the overall performance of the activated foam. In conditions of rapid carburization of the Fe NPs (pCH4 > 14 %), the productivity to CNMs is favoured, avoiding an initial deactivation of the active sites by fouling with amorphous carbon. After a rapid carburization, the selectivity to the different CNMs is governed by the ratio CH4/H2, and mainly by the temperature. Thus, the formation of GRMs, mainly Few Layer Graphene (FLG) and even graphene, is favoured at temperatures above 900 °C. At lower temperatures, carbon nanotubes are formed
Impact of a new palliative care consultation team on opioid prescription in a University Hospital
There are no validated measuring tools to gauge the effectiveness of a Hospital
Palliative Care Consultation Team (PCCT). One way would be to consider its effect on the
consumption of opioids expressed in total amounts and different formulations administered. We
perform this study to evaluate the impact of a hospital PCCT on the trends of opioid prescription
in a University Hospital.
Methods: A seven year retrospective study on opioid prescription was carried out in the Clínica
Universidad de Navarra. The period includes three years before and three years after the PCCT
was implemented. Prescription was analysed calculating yearly the Defined Daily Dose (DDD)
adjusted to 1000 hospital stays (DDD/1000HS). Indicators considered were the proportion of
patients treated using opioids compared to the total estimated in need of treatment (rate of
effectiveness) and the proportion of patients potentially requiring opioids but not treated who
were incorporated into the treatment group (rate of improvement).
Results: From 2001 to 2007, total opioid prescription was low in non-oncology Departments
(range: 69–110 DDD/1000HS) while parenteral morphine and fentanyl did not register any changes.
In the same period of time, total opioid prescription increased in the Oncology Department from
240 to 558 DDD/1000HS. The rate of effectiveness in the three years prior to the implantation of
the consultation team was 64% and in the three following years rose to 87%. The rate of
improvement prior to the palliative care consultation team was 43% and in the three following
years was 64%. A change in opioid prescription was registered after the implementation of the
PCCT resulting in an increase in the prescription of parenteral morphine and methadone and a
decrease in transdermal fentanyl.
Conclusion: Implementation of a PCCT in a University Hospital is associated with a higher and
more adequate use of opioids
Improvement of tensile properties by controlling the microstructure and crystallographic data in commercial pearlitic carbon-silicon steel via quenching and partitioning (Q&P) process
In the current research, a complex microstructure and crystallographic data were developed through quenching and partitioning (Q&P) process to improve tensile properties of commercial pearlitic carbon-silicon steel. Two-stage Q&P process, including full austenitization, quenching at 220 °C, followed by two different partitioning temperatures, was applied to the as-received specimen to generate a complex microstructure composed of tempered martensite, bainite, ultrafine carbides/martensite-austenite/retained austenite particles. Microstructure and crystallographic data were investigated by scanning electron microscopy, electron backscattered diffraction (EBSD), and X-ray diffraction techniques. Then, hardness and tensile properties were evaluated to confirm the improvement of mechanical properties. Dilatation-temperature curves exhibited the kinetics of martensitic and bainitic transformation during quenching and isothermal partitioning stages. The presence of nano-carbide particles inside athermal martensite was confirmed by electron microscopy due to the pre-formed martensite carbon depletion during the partitioning stage coupled with bainitic transformation. The formation of preferential atomic-compact direction in BCC (martensite/bainite) plates characterized by EBSD, could enhance ductility by providing adequate slip systems. Point-to-point misorientation analyses demonstrated a slight dominance of low angle boundaries proportion in bainitic dominance structure in Q&P-220-375 specimen, which could be used in phase characterization. Results revealed that the development of nanoscale carbide dispersed in refined bainite/martensite matrix boosted the yield and ultimate tensile strength by over 100% and 110% compared to the initial pearlitic microstructure. However, ductility reduced to half value in Q&P-220-325 and Q&P-220-375 specimens.Peer ReviewedPostprint (published version
Acute neuroinflammation elicited by TLR-3 systemic activation combined with early life stress induces working memory impairments in male adolescent mice
Toll-like Receptors (TLRs) are implicated with the pathogenesis of cognitive impairment induced by inflammation. Early life stress is associated with altered trajectories of neuroimmune signaling with implications for cognitive development. However, effects of TLR-3 activation on early life stress-related cognitive outcomes are understudied. We investigated the effects of maternal separation (MS) during postnatal development and a viral immune challenge during adolescence on working memory performance. BALB/c mice exposed to MS were separated from their dams daily for 180-min from postnatal day (PND) 2 to 15. At PND 45, animals were challenged with a single i.p. injection of either Poly (I:C) or sterile saline, and then subjected to a spatial working memory test in a Y-maze apparatus. Gene expression was determined by qPCR. Protein levels of oxidative stress markers were also assessed. A single peripheral administration of a TLR-3 agonist was able to induce working memory impairments in adolescent mice exposed to MS. At a molecular level, exposure to MS was associated with lower mRNA levels of Tlr3 in the medial prefrontal cortex (mPFC). However, when MS animals were exposed to Poly (I:C), a more robust activation of Tlr3, Il6 and Nfkb1 gene transcription was observed in these mice compared with control animals. These modifications did not result in oxidative stress. Finally, higher mRNA levels of Nfkb1 in the mPFC were correlated with lower working memory performance, suggesting that altered NF-\u3baB signaling might be related with poor cognitive functioning. These results have implications for how ELS affects neuroimmune signaling in the mPFC
Spanish "fine tuning" of language to describe depression and anxiety
On screening tools for emotional distress, the terms "depression" and "anxiety" are commonly used for patients with advanced cancer. However, these terms could have negative connotations in Spanish such that cultural and unexpected differences in perception may invalidate or skew the results of the screening if the best terms are not chosen. The goal of this study was to determine the best expression that can be used to explore anxiety and depression in Spanish. A prospective study of 100 Spanish-speaking patients was performed. Spanish patients with cancer completed the Hospital Anxiety and Depression Scale (HADS) and six Verbal Numerical Scales (VNS) exploring the level of anxiety using the terms ansioso (anxious), nervioso (nervous), or intranquilo (uneasy/disquiet), and the level of depression using the terms deprimido (depressed), desanimado (discouraged), or triste (sad). The correlation, sensitivity, and specificity for all the VNS and HADS (8 and 11 cutoff points) were analyzed. The correlation (Spearman rho) between HADS and the anxiety VNS was r = 0.557 using "anxious"; r = 0.603 using "nervous"; and r = 0.594 using "uneasy." The correlation for the depression VNS was r = 0.662 using "depression"; r = 0.759 using "discouraged" and r = 0.596 using "sad"; alpha < 0.001 was used in all VNS. A cutoff point of 4 of 10 for any term used to explore anxiety achieved the best levels for sensitivity (0.80) and specificity (0.70). The term "discouraged" with a cutoff point of 4 of 10 shows a sensitivity of 0.89, a specificity of 0.84, as well as a predictive positive value of 0.77 and a negative value of 0.93. In Spanish, the term desanimado seems to be more suitable in screening for depression. Alternate terms could be used to explore anxiety in Spanish. Exploring depression with simple questions in Spanish achieves greater accuracy than the same approach to exploring anxiety
What is the best term in Spanish to express the concept of cancer-related fatigue?
Introduction: Fatigue is one of the most frequent symptoms in patients with cancer. No adequate term in Spanish has been defined to describe the English concept of fatigue.
Aim: To identify the most suitable Spanish words that define the concept of fatigue and to check psychometric characteristics.
Method: Consensus with professional experts on Spanish words that best suit the English concept of fatigue. A prospective study on oncologic patients was also undertaken, which included an evaluation of the intensity of fatigue through visual numeric scales (VNS) where the words had been previously selected. The fatigue subscale of the Functional Assessment of Cancer Therapy-Fatigue (FACT-F) questionnaire was taken as a reference.
Results: The experts highlighted the words cansancio, agotamiento, and debilidad (tiredness, exhaustion, and weakness) as the terms that best defined the concept of fatigue. In the psychometric assessment study, 100 patients were included, of which 61 (61%) presented diagnostic values for cancer-related fatigue in the FACT-F fatigue subscale (score 34/52 or lower). The VNS for the chosen terms obtained a high correlation with the FACT-F fatigue subscale results: cansancio (tiredness) r = −0.71, agotamiento (exhaustion) r = −0.74, debilidad (weakness) r = −0.74, with no statistical differences between them. For the detection of fatigue by means of the VNS, tiredness (cutoff point ≥4/10) gave sensitivity (S) 0.90 and specificity (E) 0.72; exhaustion (cutoff point ≥3/10) S 0.95 and E 0.90 and weakness (cutoff point ≥4/10) S 0.92 and E 0.72. The ROC curve was 0.88 for tiredness, 0.94 for exhaustion, and 0.92 for weakness, with no significant difference between the areas mentioned. The terms cansancio, agotamiento, and debilidad (tiredness, exhaustion, and weakness) are suitable for defining the English concept of fatigue in Spanish, and should be the preferred option for inclusion in evaluation tools
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