249 research outputs found
La prima de riesgo recargada en un seguro de rentas: Tarificación mediante el uso de una medida de riesgo coherente
The goal of this study is to get a premium calculation principle, for the life insurance business, based on a coherent risk measure (Wang, 1995) in the form of power, called \Proportional Hazards (PH) Transforms" to justify the recommendation of Solvency II to reduce the effect of the mortality instantaneous rate and thus get an implicitly surcharged premium to deal deviations of actual claims regarding expected. Survival life insurance has been selected for this research, and the premium risk has been calculated for the four accepted laws of survival, such as the first and second Dormoy, Gomperzt law, and Makeham law. The selection of these laws has been taken because they best _t the model based on the numerical values assigned to the parameters by using mortality tables developed by Pérez (2000), Projected Table 2000 Spanish Mortality from 1950-1990. In the life insurance, coverage claims survival negative experience for the company means that the insured survive longer than expected (live longer). Thus, when calculating premiums, it is common practice to add a safety margin implied, as a percentage, the odds of death qx, or use a mortality table whose chances of passing are lower than those of the human being taken into account. This can be interpreted as a decrease of the mortality instantaneous rate. In this paper we show that the use of the distortion power function, so far uses in the non-life branch and being the new application to the life insurance, produces the same effect, but calculating a implicitly surcharged premium
Bioethics for Biotechnologists: From Dolly to CRISPR
Abstract: Bioethics, as a discipline, has developed mainly, but not exclusively, around themes of moral importance for the medical practice, such as abortion and euthanasia, a never ending discussion that has been shaped by social mores and influenced by scientific and technological advance. However, in the past 20 years an important shift has been taking place, one where bioethical issues and their discussion are starting to being driven by the so-called emerging biotechnologies, from cloning to genome sequencing and editing. If Bioethics is concerned with human beings, and their interaction with other living beings and the environment, it makes sense for Biotechnology, by definition the use of living systems or organisms to develop products, to become an important, if not the most important, source of bioethical conflicts in modern era and for future society. As Biotechnology keeps expanding and becomes entangled in everyday life, so does the need for ethical competent biotechnologists, with competencies built not only on ethical principles but also on a realistic grasp of the impact these technologies could have on human society and the world we inhabit.
Keywords: Biotechnology, genome editing, animal cloning, ethics, fairness, biothreats, biosafety, biosecurit
Perception of the sport events held in a permanent facility: the case of the Madrid Sports Palace
The aims of this study were to analyse perceptions regarding the sporting events held in the Madrid Sports Palace and to analyse whether those perceptions vary by age or gender. One hundred and ninetyfive residents answered the Ntloko and Swart (2008) questionnaire. The dimensions most highly rated were economic benefits (3.9±0.8), the event as a regional showcase (3.6±0.7), and the event as entertainment (3.4±0.6). However, the respondents did not agree with the negative environmental impact (2.0±0.8). Men rated the use of public money (z=2.4; pmenor que.05) and the regional showcase (z=2.0 pmenor que.05) more positively than women. Finally, women rated the increase in prices (z=2.0; pmenor que.05) more highly than men. The age groups differed significantly only regarding the promotion of community pride. Seniors and middle-aged adults rated it more positively than young adults (?2(2)=9.9; pmenor que.01). The fact that in an urban sports facility regular sporting events take place on a regular basis means that there are diverse perceptions, though mainly positive, and those perceptions differ from the perceptions about mega events that take place once in a life time at temporary sports facilities
Roll of Mrf4 gen in homeostasis of adult skeletal muscle.
Myogenesis is the process that controls skeletal muscle growth during embryonic and postnatal development, and it is orchestrated by a family of four transcription factors (TFs) known as MRFs (Myogenic Regulatory Factors)(1). Our group is working on the function of two of these genes: Mrf4 and Myf5. We and others have established a link between MRFs function and muscle atrophy/hypertrophy (2).
Mrf4 is the only MRF highly expressed in all adult skeletal muscles, but a complete understanding of its function is lacking as previous KOs models affect Myf5 expression in cis (3). Recently, our group has generated two new KO alleles using CRISPR technology (Mrf4 L1/L1 and Mrf4 L2/L2). Preliminary data shows that both alleles develop mild muscle hypertrophy, without affecting Myf5 expression in cis. Experiments in vivo indicate that the two alleles have alterations in muscle metabolism.
This project is focused on elucidating how this TF is involved in muscle growth, function, and homeostasis. Furthermore, as adult satellite cells emerge from embryonic founder cells in which Mrf4 expression was activated, we are also studying Satellite Cell biology and function in the absence of Mrf4.
Surprisingly, we have identified important phenotypic differences between the two alleles; one hypothesis is that one or both may generate a small peptide that modifies the phenotype.
Methods: We dissected the extensor digitorium longus muscle, isolated myofibers from young (3 months) and old (24 months), WT and Mrf4-/- mice, and divided these in three groups: 1- Fibers were fixed and permeabilised for immunostaining with Pax7 antibody to study the myofiber size and content in satellite cells/nuclei; 2- Fibers were plated for bioenergetic analysis using a XF24e Seahorse Analyzer that provides oxygen consumption rate as indicator of mitochondrial respiration as a proxy for metabolic function; and 3- Fibers were plated in proliferation medium to allow their associated Satellite Cells to abandon the niche, migrate and proliferate, and we studied parameters of Satellite Cell proliferation and differentiation.
In order to study the potential effect of small peptides generated by one or both alleles, we generated overexpression plasmids containing the sequences of interest. C2C12 myogenic cells were co-transfected with a GFP-expression vector using the electroporator BTX Gemini and then selected to determine if there were significant differences in proliferation and differentiatio
Comparative Analysis of the Physicochemical and Biological Characteristics of Freeze-Dried PEGylated Cationic Solid Lipid Nanoparticles
Cationic solid-lipid nanoparticles (cSLNs) have become a promising tool for gene and RNA therapies. PEGylation (PEG) is crucial in enhancing particle stability and protection. We evaluated the impact of PEG on the physicochemical and biological characteristics of cholesteryl-oleate cSLNs (CO-cSLNs). Several parameters were analyzed, including the particle size, polydispersity index, zeta potential, shape, stability, cytotoxicity, and loading efficiency. Five different formulations with specific PEGs were developed and compared in both suspended and freeze-dried states. Small, homogeneous, and cationic suspended nanoparticles were obtained, with the Gelucire 50/13 (PEG-32 hydrogenated palm glycerides; Gelucire) and DSPE-mPEG2000 (1,2-distearoyl-phosphatidylethanolamine-methyl-polyethyleneglycol conjungate-2000; DSPE) formulations exhibiting the smallest particle size (similar to 170 nm). Monodisperse populations of freeze-dried nanoparticles were also achieved, with particle sizes ranging from 200 to 300 nm and Z potential values of 30-35 mV. Notably, Gelucire again produced the smallest particle size (211.1 +/- 22.4), while the DSPE and Myrj S100 (polyoxyethylene (100) stearate; PEG-100 Stearate) formulations had similar particle sizes to CO-cSLNs (similar to 235 nm). The obtained PEGylated nanoparticles showed suitable properties: they were nontoxic, had acceptable morphology, were capable of forming SLNplexes, and were stable in both suspended and lyophilized states. These PEG-cSLNs are a potential resource for in vivo assays and have the advantage of employing cost-effective PEGs. Optimizing the lyophilization process and standardizing parameters are also recommended to maintain nanoparticle integrity
New materials for gas separation applications: Mixed matrix membranes made from linear polyimides and porous polymer networks having lactam groups
Producción CientíficaA set of mixed matrix membranes (MMMs) has been prepared by incorporating a triptycene-isatin porous polymer network (PPN) to three aromatic polyimides (one commercial, Matrimid, and two synthesized by us: 6FDA–6FpDA and 6FDA–TMPD) covering a wide range of performances for gas separation. The triptycene-isatin PPN is a highly microporous network having a high CO2 uptake and high chemical and thermal stability. The good compatibility between the components (PPN content of 15 and 30% w/w) was supported by the increase in the glass transition temperature of MMMs relative to the pure polyimide membranes. The addition of the PPN particles improved the permeability of all the gases tested, by increasing diffusivity and, in some cases, gas solubility. The improvements were particularly noticeable in Matrimid-based MMMs, where gas permeability increased by 700%, whereas CO2/N2 and CO2/CH4 ideal selectivities decreased by a mere 4% and 12%, respectively.Ministerio de Economía, Industria y Competitividad (projects MAT2016−76413-C2-R2, MAT2016− 76413-C2-R1, MAT2015−69844-R and CTQ2016−80913- P)Junta de Castilla y León (projects VA248U13 and VA051P17
Plant-Derived Bioactive Compounds for Rhabdomyosarcoma Therapy In Vitro: A Systematic Review
Rhabdomyosarcoma (RMS), the most common soft tissue sarcoma in children, constitutes
approximately 40% of all recorded soft tissue tumors and is associated with a poor prognosis, with
survival rates of less than 20% at 3 years. The development of resistance to cytotoxic drugs is a
primary contributor to therapeutic failure. Consequently, the exploration of new therapeutic strategies
is of vital importance. The potential use of plant extracts and their bioactive compounds emerges as a
complementary treatment for this type of cancer. This systematic review focuses on research related
to plant extracts or isolated bioactive compounds exhibiting antitumor activity against RMS cells.
Literature searches were conducted in PubMed, Scopus, Cochrane, and WOS. A total of 173 articles
published to date were identified, although only 40 were finally included to meet the inclusion
criteria. Furthermore, many of these compounds are readily available and have reduced cytotoxicity,
showing an apoptosis-mediated mechanism of action to induce tumor cell death. Interestingly, their
use combined with chemotherapy or loaded with nanoparticles achieves better results by reducing
toxicity and/or facilitating entry into tumor cells. Future in vivo studies will be necessary to verify
the utility of these natural compounds as a therapeutic tool for RMS.Spanish Ministry of Science and Innovation
(FEDER) (CPP2022-009967 and CPP2022-010017)Spanish Ministry of Universities and Science
(RTC2019-006870-1
Porous organic polymers containing active metal centers for Suzuki–Miyaura heterocoupling reactions
Producción CientíficaA new generation of confined palladium(II) catalysts covalently attached inside of porous organic polymers (POPs) has been attained. The synthetic approach employed was straightforward, and there was no prerequisite for making any modification of the precursor polymer. First, POP-based catalytic supports were obtained by reacting one symmetric trifunctional aromatic monomer (1,3,5-triphenylbenzene) with two ketones having electron-withdrawing groups (4,5-diazafluoren-9-one, DAFO, and isatin) in superacidic media. The homopolymers and copolymers were made using stoichiometric ratios between the functional groups, and they were obtained with quantitative yields after the optimization of reaction conditions. Moreover, the number of chelating groups (bipyridine moieties) available to bind Pd(II) ions to the catalyst supports was modified using different DAFO/isatin ratios. The resulting amorphous polymers and copolymers showed high thermal stability, above 500 °C, and moderate–high specific surface areas (from 760 to 935 m2 g–1), with high microporosity contribution (from 64 to 77%). Next, POP-supported Pd(II) catalysts were obtained by simple immersion of the catalyst supports in a palladium(II) acetate solution, observing that the metal content was similar to that theoretically expected according to the amount of bipyridine groups present. The catalytic activity of these heterogeneous catalysts was explored for the synthesis of biphenyl and terphenyl compounds, via the Suzuki–Miyaura cross-coupling reaction using a green solvent (ethanol/water), low palladium loads, and aerobic conditions. The findings showed excellent catalytic activity with quantitative product yields. Additionally, the recyclability of the catalysts, by simply washing it with ethanol, was excellent, with a sp2–sp2 coupling yield higher than 95% after five cycles of use. Finally, the feasibility of these catalysts to be employed in tangible organic reactions was assessed. Thus, the synthesis of a bulky compound, 4,4′-dimethoxy-5′-tert-butyl-m-terphenylene, which is a precursor of a thermal rearrangement monomer, was scaled-up to 2 g, with high conversion and 96% yield of the pure product.Agencia Estatal de Investigación (projects PID2019-109403RB-C22, MAT2016-76413-C2-R2, CTQ2017-89217- P and MAT2016-76413-C2-R1)Junta de Castilla y León (project VA038G18
New Insights in the Synthesis of High-Molecular-Weight Aromatic Polyamides-Improved Synthesis of Rod-like PPTA
Producción CientíficaBy employing a variation of the polyamidation method using in situ silylated diamines and acid chlorides, it was possible to obtain a rod-type polyamide: poly(p-phenylene terephthalamide) (PPTA, a polymer used in the high-value-added material Kevlar), with a molecular weight much higher than that obtained with the classical and industrial polyamidation method. The optimization of the method has consisted of using, together with the silylating agent, a mixture of pyridine and a high-pKa tertiary amine. The research was complemented by a combination of nuclear magnetic resonance and molecular simulation studies, which determined that the improvements in molecular weight derive mainly from the formation of silylamide groups in the growing polymer
Pyrrolidine-based catalytic microporous polymers in sustainable C=N and C=C bond formation via iminium and enamine activation
Producción CientíficaA new set of catalytic materials having a pyrrolidine moiety confined in microporous organic polymer networks (POPs) has been attained. These catalytic polymers have been prepared by a straightforward synthesis starting from microporous polymer networks made from isatin (or a mixture of isatin and trifluoroacetophenone) and 1,3,5-triphenylbenzene. The polymers efficiently catalyzed the formation of nitrones under very mild and sustainable conditions using green solvents through an iminium ion activation mechanism. The reactions are scalable, and polymers are easily recycled. Special attention has been paid to understanding all the factors that could affect the efficiency of the confined catalysts. The electronic and conformational characteristics of the pyrrolidine moiety attached to the porous polymers, as well as other features that could affect the transport through the network, such as molecular volume and shape of reactants and products, and even hydrophilic or hydrophobic properties, have been systematically evaluated. In addition, the heterogeneous polymers are also useful in Cdouble bondC bond formation through both iminium ion and enamine activation.Gobierno de España (Agencia Estatal de Investigación) - (Projects CTQ2016-78779-R, PID2019-109403RB-C22, RTI2018-096328-B-I00, CTQ2017-89217-P and PID2020-118547GBI00)Junta de Castilla y León, Unión Europea y Fondo Europeo de Desarrollo Regional (FEDER) - (Project VA224P20)
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